All the answers below were contributed by John Booth CGAE (aka Doc John) -
John was in the trade 40 plus years; as a conscientious and dependable professional in all aspects of the industry, he has excellent analytical and assessment skills, recognized for a high degree of integrity and dedication to the cause.
Anti Freeze in Oil - Anti Freeze in Oil
Anti Freeze in Oil
Will anti-freeze (Green type) in the oil hurt the engine if it is driven about 350 miles after detection. The engine never cooled down and the oil was flushed twice after arriving at the destination. It is a GM truck with a 6.5 liter diesel.
Will Green type anti-freeze in the oil hurt the engine? Matt , Anti-freeze of any kind can cause damage to an engine.
The problem with anti-freeze in the engine oil is that you cannot tell from the outside what damage may or may not have occurred. You did the right thing by flushing that anti-freeze out of the system. I hope that you had the cause for anti-freeze entering the engine oil corrected as well.
At this point you have two approaches to your question. 1) You can have the engine disassembled and inspected. 2) You can test your luck and run the engine to see what happens.
Continental - check power assist
Continental
It seems when I'm parking and turn the steering wheel it becomes really stiff and I get a "check power assist" message . It only does this when I'm in a tight spot and really turn the wheel hard. Once I turn off the car the steering is back to normal.
It sounds as if your Continental is equipped with an Electronic Variable Orifice (EVO) system. EVO is an elegant way to say computer assisted, assisted power steering. Are you with me? You have a highbred type of power assisted steering on your vehicle that has 3 basic forms of operation; full power steering assist at low speed for parking effort, minimum assist at high speed for good road feel and directional stability, and high assist at high speed for evasive maneuvers, for dodging suicidal squirrels crossing the road. The Vehicle Dynamics Module (VDM) alters the characteristic of the power steering system based on inputs from different computer sensors on the vehicle. If the Check Power Assist warning light is coming on there is likely a diagnostic trouble code in the computer that can be retrieved that should explain your loss of power assist. With this information the corrective repairs can be made.
Crown Vic - oil pressure light
Crown Vic
I have a '91 Crown Vic with 122,000 miles on it. Lately the oil pressure light comes on, but only when the car is FULLY warmed up and ticking over while stopped. I'm pretty sure the pressure is low because I can hear a little rattling in the lifter department. It seems like the problem may be what controls the idle at high operating temperature. For
example, if I take all load off the engine: turn off A/C and put transmission in park, the idle pops right back to a level which provides adequate pressure. It will even stall out while idling at a red light as the idle speed gets too low. Do you have any ideas?...
There are a couple of items you should have checked Jay. The idle speed is computer controlled and should not be dropping to the level that would create a stalling condition. The likely cause is a failed IAC
(idle air control) valve. It doesn't take long to diagnose a failed idle air control valve. Too low of an engine idle speed on a vehicle of the age/mileage could allow oil pressure to drop to the warning level. If the problem remains after the idle speed is corrected then have a mechanical oil gauge installed to check the engine oil pressure readings. This would aid in determining if your problem is a serious one or just age showing up.
Also, don't be afraid to change the oil from a 5w-30 to a 10w-30 or 40.
A little heavier oil can make a difference in preventing metal to metal
contact in older engines.
Bonneville - battery, which is new, is overcharging
Bonneville
Doc John, You have come to my rescue in the past, and I hope you will be able to provide assistance again.
The battery, which is new, is overcharging in my 64 Bonneville. The reading on the meter is at 17! I replaced
the voltage regulator, checked to ensure that it is properly earthed, and it still overcharges (and leaks). The
earth straps appear to be grounded to earth. If I remove the leads to the voltage regulator, the readings on the meter obviously drop. Could the alternator need replacement? I don't believe the alternator is the problem since it is, in fact, charging. Any advice or suggestions are greatly appreciated! Oh, also, when I turned on the
headlights, the reading dropped from 17 to 14...I'm not sure if that tells you anything. Thanks.
We'll have to do some detective work here.First, you'll have to tell me what kind of meter you are using, and exactly where you are connecting it. Also, measure the voltage between the two battery posts (not on the cable ends, put your test probes right on the round posts of the battery), and measure this voltage before you start the car, then again after the car is running, with no lights on or any other heavy load.From this information, we can probably track down the problem. For your info, the voltage on the battery posts with the engine running and no lights or other heavy loads should be about 14.4 volts when the battery is fully warmed up, higher if the battery is cold. The voltage on the battery posts when the engine is off, and has been off for at least an hour or so, with nothing at all on in the car, should be about 12.8 or 12.9.Let me know what you find out and we'll go to step 2!
newport - heater
newport
my rear defog & heater/AC blower motor wont run. The fuse is good. I jumped the motor with a hot lead
& it does operate. I've heard there may be some sort of interior resistor, not sure what it would look like
& where its located. Please advise. Thanks
There is a resistor in the circuit, but it only affects the lower speeds. If it won't run on any speed, thereis something else wrong.If your car has automatic temperature control, the master switch is probably bad - it is a vacuum operated switch on the air plenum with two wires going to it, and a vacuum hose. It is either yellow or green in color - or you may have both. One controls the AC compressor, the other controls the whole HVAC system. These switches are shaped like mushrooms, about 1 inch in diameter. If you have these, just jumper across the two terminals - if that brings the system on, you know that either your vacuum hose is not connected to the source, or the switch is bad (or else you have poor intake manifold vacuum).If your car does not have ATC your problem could also be in the main system control, or the fuse could be making poor contact in the socket - you'd best get a 12 volt test light from the auto parts place and poke around to find the problem - it shouldn't be hard to track down.
Petrol Savers - Do the petrol savers really work
Petrol Savers
I see the adverts on the telly for petrol savers and I think it sounds too good to be true. So, do the petrol savers really work and, save you money?
Paul, Here's my thoughts on these marvels of technology that have eluded engineers from all of the car and truck manufacturers. Just imagine a miracle product that would increase horsepower and gas mileage! After all, if you've gotten better gas mileage it would mean you also reduced emissions! The world's dependency on oil would be washed away! If it is truely a mavel of technology and it really really works the inventer would be rich and living on an island not pushing their wares on TV infomercials. So don't waste your money Paul.
Coolant - Can I Mix them? - Mix coolants
Coolant - Can I Mix them?
Can I mix GM Dex Cool with conventional coolant? I have heard that if the two are mixed together they will gum-up.
Dan, I have mentioned this before in previous articles and, it's always a good idea to keep repeating it. Never ever mix a long/extended life anti-freeze with what is becoming the old type green anti-freeze. We are seeing a mixing problem not only with GM's long life but with many other manufacturers as well. Not only North America but also many of the Asian and European vehicles now specify a long life coolant that is not compatible with commonly known used green anti-freeze.
If you mix the different coolants, you're looking for trouble. In the event you do mix the two have the cooling system drained and flushed. Rule of thumb is at least a minimum of three system flushes to rid the bad mix. In today's vehicles you have to know what you're adding to the cooling system; it's not a simple as it use to be.
Coolant - Brown rusty Sludge
Coolant
I've read your article about Dex Cool and the horror stories about this long life coolant. I've just bought a 2001 Pontiac Firebird with 35,000 miles on it. I checked the coolant level and found some brown looking rust coloured stuff on the cap. Is this normal? How can I tell if it needs to be changed?
It definately sounds as if your vehicle's cooling system needs service Andy, and it's a good thing you're checking under the hood. This long life coolant that GM has been using in their vehicles has been really odd. In some vehicles, the stuff works great and stays low in acidity with good clarity. On other vehicles the stuff doesn't last 2 years without making that brown stuff you've noted. The problem with the long life antifreeze is once it gets out of control it's is a disaster to deal with. Also, we've have found that people have been mixing the old style green anti freeze with the orange long life. That is a big no-no! Never mix the two coolants together. Have your cooling system flushed at least three times and refilled and don't forget the coolant reservoir, it needs to be drained and cleaned as well.
Auto laws on repairs - Auto laws on repairs (What they can or cannot do)
Auto laws on repairs
Anywhere I can find out about what auto laws on repairs done by an auto repair shop and what about repairs that were not done right? What about ones you didn't give them permission to do?
About anyone can guess why you might be asking such questions. The first thing I would suggest to you is to organize your concerns on paper. You need to have your facts in order with documentation. Once you've done this, contact the repair facility and speak with the owner. Review these concerns and ask if he or she would be willing to address these issues/concerns and come to an agreement. Many times there is a loss of communication that results in confusion and unhappy parties over repairs. Most importantly maintain control, don't let you emotions run the conversation, even if some tongue biting is needed.
Some controlled and stable time on the phone can be productive for both parties involved. If this doesn't work just end the conversation with I'm sorry we couldn't work this out. After that, call the better business bureau. They can guide you on the laws and rights you have as a consumer. If you've been wrongly charged for repairs then you do have rights and recourse available to you.
Check to see if any Bills were passed to help with these concerns and outlines what the garage has to do when dealing with every customer, his/her rights and the garages rights. This bill if there is such a beast was introduced to protect both the business and the consumer. Type in " Consumers Rights. " on your search engine and find one dealing with garage repair.
2WD - Shocks recommendation
2WD
What brand of rear shocks do you recommend for a 95 2WD? I haul some fairly heavy things and it sags a good bit. I am currently running factory shocks. Thanks for the advice.
First Vaughan, the job of the shock absorbers is to keep the tire on the road; they are not designed to lift a vehicle. But, there are shock absorbers that are modified to assist in maintaining the ride height of a vehicle. The modified shocks are generally found in 2 configurations: air assisted (known to many as air shocks) and coil assisted (shocks with coil springs). The coil assisted shocks are designed to maintain vehicle ride height with about 200 lbs. of additional weight in the vehicle, rates vary depending on manufacturer. Air assisted shocks have air lines that join together at a fitting that looks similar to a tire valve stem. The air pressure can be increased or decreased as needed to maintain the vehicle's ride height. Check the manufacturer's specification regarding the additional load abilities of these shocks. If the load you're carrying is greater than the manufacturer's recommendation then consider installing stronger springs with heavy duty shocks.
Impala SS - Noises like exhaust leak
Impala SS
I have a '95 Impala SS. It sounds like it has an exhaust leak, when the engine is first started. After driving for about 10 minutes or so it goes away. Can you help?
If it sounds like an exhaust leak, it probably is Shaun. While the engine is cold, closely inspect the exhaust manifolds primarily near the rear of the engine; that's where the problems most commonly are found. Usually you'll find that a bolt has loosened up allowing the exhaust manifold to pull away from the engine. As the engine heats up the exhaust manifold expands closing the exhaust leak. I would recommend having the problem corrected before it gets worse or requires additional parts and labor.
Taurus - AC compressor problems
Taurus
I just had a rebuilt engine put in my '93 Taurus and the mechanic left the A/C hose unhooked from the compressor because he said my car was empty of freon. I did not have a problem with my A/C before. He said it would burn out the compressor if it was left hooked up without any freon. I think it should have stayed hooked up so trash and etc. stay out of it. Who's right?
You are right, he’s wrong! Get that A/C hose hooked back up ASAP! The refrigerant in today’s vehicle’s not only removes heat from the passenger compartment. It also carries the lubricant that is critical to the A/C compressor. There is a low pressure switch that automatically shuts down the A/C system if there is not enough refrigerant in the system preventing major damage. Keeping an A/C system closed up also prevents dirt and moisture from entering the A/C system. Moisture causes damaging acids to form inside the A/C system. Plus just don't go back to that garage again, unless you wnat to ask him to hook the hose up again and then tell him why.
2WD Day Van - Rear Shocks recommend
2WD Day Van
What brand of rear shocks do you recommend for a '95 2WD Day Van? I haul some fairly heavy things sometimes and the vehicle must be weighted down for traction in winter. When I weigh it down, it sags a good bit. I am currently running factory shocks. Thanks for any advice
First, the job of the shock absorbers is to keep the tires on the road, and to dampen road surface oscillations, they are not designed to lift a vehicle. But, there are shock absorbers that are modified to assist in maintaining the ride height of a vehicle. The modified shocks are generally found in 2 configurations: air assisted (known to many as air shocks) and coil assisted (shocks with coil springs). The coil assisted shocks are designed to maintain vehicle ride height with about 200 lbs. of additional weight in the vehicle, rates vary depending on manufacturer. Air assisted shocks have air lines that join together at a fitting that looks similar to a tire valve stem. The air pressure can be increased or decreased as needed to maintain the vehicle's ride height. Check the manufacturer's specification regarding the additional load abilities of these shocks. If the load you're carrying is greater than the manufacturer's recommendation then consider installing stronger springs with heavy duty shocks.
The Ooey Gooey Carburetter - The Ooey Gooey Carburetter
The Ooey Gooey Carburetter
I have a secondary car I rarely drive. Recently, I had a weird problem that I cannot explain. Picture this: I'm driving along in mild traffic and suddenly get a bunch of smoke out the exhaust pipe (whitish in color, I think). I get through the first light but the engine dies at the next light and I can't restart it. The car was not overheating and had only run for a few miles. I checked the oil andit was all very creamy. I thought I must have blown a head gasket. Then I noticed all this creamy goo inthe air filter and carburetter as well; very puzzling. After getting it towed home I cleaned out all thegoo in the intake system and flushed out the carburetter. It started right up and ran great. I changed the oil and filter as well. Now the car runs very well, has no signs of water in the oil and no loss of coolant. I can only guess that maybe from the rains, water got into the gas filler cap and after I filled up the tank it all got sucked in. But how do I explain the water in the oil? What happened?
The problem is likely a combination of events. Water can't get from the gas tank to the engine oil. Water in the gas will get into the carburetor and cause a running problem. The creamy goo you're describing is probably blow-by from the crankcase. This goo clogged the air filter, causing the engine to stall. The reason for the goo? Check the PCV valve; it is most likely restricted or plugged causing crankcase gasses to be forced out the vent into the air cleaner assembly.
Malibu - Problems relating to Anti-Theft device etc.
Malibu
Hi doctor John
Thank you so much for your prompt reply, my aplologies, the car in a 2000 Malibu, VIN # (Removed for security) , and its owned by my daughter and son in law. Your help is greatly appreciated.. The Body control module has been replaced at a cost of approx. $800, but dealership do not know where the leak is, and suggested it not be driven in the rain, we are to find someone to try to find the problem. thank you Eithne/Harry
Hi Harry! Well what I was going to suggest was that if they say this is the problem, make sure you get it in writing from them, that having paid for it, " if it turns out not to be the problem I want the old part back in and a refund! " Always ask for you old parts, you never know if it came to retaking the garage to court at least you still have the evidence. One the garage has throw it away your stuck paying for the part even though it's not the problem.
Of course now it's in, so hopefully that will take care of the problem. On your vehicle there is a BCM and an ECM they both 'talk' to each other and swap information appertaining to the runability of the vehicle. Now had I have been doing the job, before putting the new module in. I would have put someone in the vehicle with a trouble light and I then would have fine sprayed the outside of the car ( simulating rain ) while the guy inside looks under the dash to see where the water is coming in.
I would have concentrated the water on quite a few places, one being the cold air vents just below the windshield. What happens with this is that under this cowling are two drain holes, as time goes on, dirt, crud, and leaves get in there and the leaves start to plug-up the drainage holes..............
You start to get a little pool of water, this pool level gets higher each time it rains until it gets to a point in the sheet metal that hasn't been sealed well at the factory, then the water now drips down into the interior, either under the drivers carpet or the passengers carpet, and gradually creeps along to the module and corrodes it, wetting the carpet as it goes.
The Pontiac Grand-Am had this problem, their air bag module was under the seat, it wasn't a sealed unit, water would corrode it and the air bag would go off without any warning while you were driving........very dangerous!
I don't understand why the dealership service manager, or a technician couldn't take the time to find the leak for you, after all customers service and PR work go hand in hand and he would have kept you as a satisfied customer and a happy one...
So you might try doing what I have suggested with a buddy and see what you find. the other places water could get in are the windshield wiper pivot spindles which pass through the cowling also. Or perhaps a body drainage rubber grommet has fallen out of the under floor of the car. Perhaps the weather stripping on the forward part of the drivers door or passengers door is faulty and letting in water thrown up by the wheel when driving.
G20 Vandura Dayvan - Brake master cylinder
G20 Vandura Dayvan
I would like technical help re the brake master cylinder on a 1989 G20 VANDURA
DAYVAN. When I depress the brake pedal to bleed the brakes it fountains into the
reservoir. Is this a fault - doesn't seem right to me.
Do I need a master cylinder overhaul kit?
Hi Dave! When bleeding brakes this is normal, that's why you always have to keep the top on the m/cylinder when bleeding otherwise you'll get it spurting all over the paint.......removes paint really well, unless you have silicone brake fluid then it wont harm the paint.
Just remember when bleeding, start with opening the farthest bleed nipple from the m/cylinder first, which if it's left-hand drive will be the right rear, then do the left rear, then the front right, and finally the nearest one to the m/cylinder, the front left. Also remember to check the m/cylinder frequently when bleeding as you don't want the level to go down to the point you'll be sucking air into the master.
Synthetic Oil - May not benefit the older engine
Synthetic Oil
Hi Doc
You mentioned in last months mag that synthetic oil would benefit all engines whatever the age. Now I've just read in Classic American (August-an article on saving petrol) that synthetic or semi-synthetic oils may not benefit the older engine! Hopefully you were right as I've just changed my oil for semi-syn!! Only difference I've noticed is slightly lower oil pressure-is that a problem? Cheers Doc,
Hi Dave!
Well I am not the only one that thinks that synthetic is the way to go, but all the articles I have read in many SAE ( Society of Automotive Engineers ) magazines say the same. Putting it briefly, when choosing a full synthetic-based lubricant you're choosing advanced technology, increased efficiency, increased longevity and better control over your oil consumption.
For one the benefits are far superior than mineral based oils. With full synthetics you get as I have said...
- Greater high temperature stability
- Improved deposit control
- Superior low temperature pumpability for far quicker circulation, especially in cold weather ( what's known as cold starts create the most wear on an engine, that crucial time when there is almost nil oil on metal parts ).
- Has greater oxidation resistance.
- Great shear stability
- Has low volatility giving lower oil consumption
- Reduces friction for improved economy, increases horsepower and gives you a cooler running engine.
So with less friction, comes less heat in the engine, which helps increase gas mileage............now can mineral oil boast about all these things. With high mileage engines you should be using 5W 50 available from Castrol Syntec This is what I use in all of my vehicles...I wouldn't mind knowing why it's bad for high mileage engines, though that article covered themselves by saying..." It may? "
Better pumpability gives you slightly lower oil pressure but as long as you have around 25 -30 + psi at Idle and 55 - 60 + at speed your okay...Next time you change your oil, buy full synthetic, semi doesn't have as many attributes as FULL synthetic.
Also because it doesn't break down as quickly as mineral oil, you can extend the mileage to around 5,500 miles instead of the usual mineral oil change time of 3,000 miles, if you want to. This depends of course on whether you do very frequent short journey's , whereby the engine doesn't reach normal operating temperatures to burn off the crud, acidity, and condensation a cold engine start produces, in that case change at 3,000 miles.
Synthetic Oil/ Organic Oil? - Synthetic Oil vs Organic Oil?
Synthetic Oil/ Organic Oil?
In the May issue American Auto News you stated " No matter how old your car is it can benefit from using synthetic oil " but Steve Trice from USAutomotive says DO NOT USE synth. in my 1980 Chevy Monty 267 V8. I drained the GM synth and replaced it with GTX dinosaur oil but find the initial start/run sluggish compared to the synth. If you say it's OK I would like to use Mobil 1 ( use this in my Harley 4yrs ) my handbook says 10/40 but Mobil doesn't do this grade in fully synth. Could I use another grade ie. 5/40 or even 0/40 ? only 60,000 + on this engine, no cat. air con egr pcv air pump removed..4brrl Holley..Edelbrock Perf. MSD ign module
No you can't be the Duke of Guernsey, well you might when driving the Monte Carlo
...I wonder if USAutomotive said why not to use synthetic oil?
Well I could write a whole page on why these synthetic oils are far superior than mineral oils. You might want to use it also in the transmission the next time you have that serviced, synthetic transmission fluid helps dissipate heat (major cause of trans problems)much faster plus having all the additives in it much like the engine oil does.
Mobil 1 is the tops along with Castrol Syntec. You can use 5W 40 or the new rated 5W 50 if you have that on the shelves over there.
As for the emission equipment being removed, I guess your pollution laws aren't anywhere as strict as ours, if it's found removed on DOT inspection ( your MOT ) you are fined and the car has to be put back with it all working before you can get your license tag allowing you on the road. We also have mobile sniffer machines at the side of the rood, and if you drive by and it ' sniffs' too much bad emissions, there's another ticket, or they give you
48 hours to get it repaired at a State run garage. If you don't and your caught again, then they confiscate the car and it is crushed, tough if you still owe money on it ...Of course that's not in all States, they each have their own way of dealing with violations
Firebird - Excessive Oil Consumption
Firebird
Hi Doc
My vehicle is a 1997 Firebird Doc and has only 27,000 miles on it. I now have to check my oil nearly every day, as it seems to have excessive oil consumption.
It has always had regular maintenance and I have never run low on oil, the compression figures are to spec. The garage has performed all kinds of tests and cannot find why I am having this problem. Do you have any leads as to why?
With the garage giving you the fine toothcomb treatment in trying to find the culprit and coming up blank is key to letting me know why. What’s happening is the intake manifold gasket is delaminating. A common problem with these vehicles. GM now supplies an upgraded intake manifold gasket kit. Get the garage to check this out and go from there.
Fuel cut off and air bag - Fuel cut off and air bag
Fuel cut off and air bag
My son hit a bump hard enough to cause the air bag to deploy, now the car wont start. We have replaced the battery and the fuel pump and still we get nothing. We cannot find the relay to the fuel pump to reset it, or turn it back on. I hope that is all at this point. I have put a lot of money into this car in the past 6 months and I can’t afford to really put any more into it. Please help! Where is this relay switch and what else could be the problem?
Alex, are you sure this was just a bump, and not a jump? You have to jump a Ford pretty high to deploy the air bag and close the fuel cut-off switch. The Ford’s fuel system is equipped with a switch that, on sudden impact, will turn the power supply off to the fuel pump. This switch is called an inertia switch, which is located in the trunk ( boot ) of your model Ford. There is a button on the top that has to be pressed down to reset this switch. Once that is done electrical power is restored to the fuel pump and the vehicle is ready for it’s next ‘ aerial trip. ’ Another idea as well Alex would be to have the front end checked and an alignment done.
Trans Am - Rear break pads - problems changing.
Trans Am
Hi, I am having a little difficulty with changing the rear brake pads on my 1979 Trans Am.
On the passenger's side, the top bolt of the two holding the caliper in place, comes out with no problem, but the lower one is prevented from coming all the way out by the leaf spring. I have not as yet attempted the driver's side so I don't know if it is the same on that side.
Thanks in advance for any help you may be able to give.
Hi Mike!, Well I guess you have the car jacked up by the rear axle instead of the body, so that means the rear semi elliptical springs are in the way. If you jack it by the body you wont have any trouble. The disc brake assemblies are very similar to the front calipers in that they have the bushing and pin passing through it, however the pistons do not push back like the front pistons, they are on a ratchet and wind in, there is normally a special tool for this.
Also to remember is unclip the retaining clip from the cover of the master cylinder, don't remove the lid, just let it sit normally. The reason for this is that if you don't, when the pistons in the calipers are retracted they push the brake fluid back up into the m/cylinder and create a pressure so that when you open the lid it will spew all over your paint and engine. With the clip off the pressure wont build up, but any excess brake fluid will simply trickle out the sides, so before starting this job put an piece of toweling underneath
Trans Am 400 4SP - Transmission Problem
Trans Am 400 4SP
I have a 79 Trans Am 400 4SP – intermittently the transmission will not shift until I turn the car off and put the car in gear then start it. It does not seem to be a linkage issue since the shifter is smooth. This happens when stopped or idling then attempting to put the car in 1st gear – when it happens it will not go into any gear until you shut off the engine. Where should I start to look?
Hi Roland! You didn't say whether you had a Saginaw or a Muncie 4 speed transmission, or whether it is equipped with transmission controlled spark (TCS or TRS ) switch. Never mind in this case it really wouldn't make a difference to my answers except to say if it has this switch do not remove it from the transmission unless it is being replaced.
There are many reasons for clutch drag (spin ) or failure to release. The following conditions apply to unmodified versions of standard 4 speed transmissions. Clutch drag, failure to release or abnormal spin-time may be caused by the one or more of these:
- Improper clutch linkage adjustment or release off pivot fork.
- Clutch disc hub binding on the transmission input ( pinion ) shaft.
- A warped or bent clutch disc, or pressure plate; or loose friction material on the clutch disc.
- The transmission input shaft may be binding or sticking in the pilot bearing.
- Misalignment of transmission to the engine.
- Transmission lubricant low or not heavy enough.
Now apart from these I have listed there is also three very common problems associated with this. When you depress the clutch having stopped the engine and after the spin-time nothing is spinning around, it will go into gear, but the clutch disc is probably still engaged. 1) This can be caused by a film of oil on the pressure plate surface and the clutch disc. This causes a suction and therefore the release bearing though pushing the pressure plate fingers to release, the oil is causing the disc to stick and not release the two surfaces ( clutch disc & pressure plate ).
2) Can also be caused by the splines on the shaft getting rusty and therefore it will hang up the clutch plate also.
3) It can also be caused by the pressure plate springs getting very weak.
You will have to remove the transmission and if it is rust, clean the splines on the trans input shaft and the clutch inner splined ring so that neither bind when replacing.
If it's oil then you must look at either the rear main seal on the engine is leaking, or the front seal of the gearbox. If this has gotten on the clutch facing, the clutch disc must be replaced, no good trying to clean it, it will have saturated through the facings.
If the complete clutch assembly has been in there for quite some time and shows wear, it would be worthwhile changing all three parts as you have the transmission off the car. Pressure Plate, Clutch Disc , and Throw-out (Release ) Bearing should all be replaced.
If it's none of these three very common problems then you'll have to check out all the other things I have mentioned.............
As for the clutch spin-time, three seconds is a good, typical, spin-time for the transmission and clutch. What this means if you are unaware of what I mean by spin-time is that the clutch disc and some of the transmission gears spin briefly after clutch disengagement, so normal clutch action should not be confused with a dragging or sticking clutch.
American Decoke - American Decoke
American Decoke
I wonder if you can shed any light on a procedure known to me as an American Decoke which was practiced by a previous workshop manager of the garage where I now work. Instead of decarbonising an engine by stripping the head etc he’d connect a long hose to a vacuum take-off on the inlet manifold, immerse the other end in a bucket of water and then rev the guts out of the car.The engine would buck and splutter,thump and bang,all shades of smoke would belch out of the exhaust until the water had all been syphoned out of the bucket and passed through the engine,decarbonising as it went.
The procedure was carried out several times by this one same man (as no-one else had the bottle to do it ) and the art left the workshop along with him,he never hydraulic’d an engine and the procedure cured pinking,running on etc all the problems associated with a coked up engine. If the practice is a valid one it may save a lot of people a lot of expense and time, considering most of us yank drivers have two cylinder heads to sort out,but I must admit after 22 years in the workshop I’ve never heard of anyone else decoking an engine this way and I’m wondering if I imagined it all sometimes.
I remember back in the seventies there was a kit on the market over here that injected a precision amount of water into the car as you were driving, this was meant to increase horse power, was not intended as a decarbonizer.
I have actually done what you were asking about this with a woman's car when it was brought to me, she had been to garage with this knock in the engine. Now to hear this noise you would swear that the bottom end was hammering away, the garage she went to didn't make any diagnosis they just said, " you need a new engine ", $2,000.
She phoned me and I went over to her house, took my stethoscope,listened on the oil pan,
then listened on the top of the engine. This is where the noise was coming from upper part of the engine. I checked her mileage she had 231,000 on it. I then had an idea what was causing it. Carbon had built up and the piston was hitting it at the top of the cylinder.
I then mixture a quantity of water with Varsol, told the lady to hold the engine at 2,000 rpm and I carefully poured the droplets of this mixture down the carb. The crud that came out the tailpipe was unbelievable. When I had finished ( about two minutes ) she idled the engine and we checked for the noise....nothing. That was two years ago.
Now the moral of this story is, you have to know how much to dribble down the carb. You can ruin the engine very easily, because everybody that does this has high mileage and wont take a lot of banging around, things are worn as it is. What happens is the water/Varsol droplets are crystallized by the intense heat and act like sandblasting, which is all very fine. The problem is the crud that is coming out also leaves behind a lot and this can plug up the baffles in the muffler. Even worse if you have a catalytic converter on it. Now having this restriction in the Cat will cause the Cat to get white hot, melt the platinum beads into clumps and stops the exhaust from coming out.
It's not something I would condone, unless you really know what your doing. Does this guy guarantee he wont ruin your engine when he performs this? Even if he does, he can easily get out of it by saying, " well the engine has a lot of miles on it, and was probably on it's last legs anyway ". Plus the downside of this as against removing the heads is that you don't know the condition of the valves, and once his method has cleaned everything perhaps the valves wouldn't " seat " properly any more and you'll have a worse compression leakage.
If fact if you replaced the heads with a reconditioned one (pair ) on a high mileage engine, the increased compression you benefit from will knock the bottom end out fairly quickly, especially if you do a lot of freeway driving. As for calling this water process " American Decoke " I have never ever heard that expression, and I imagine it was conjured up in the UK.
351 C Ford V-8 - fire comes out of the carb
351 C Ford V-8
I have a 1972 351 C Ford V-8. It has headers and a 750 Holley carb. The car has been sitting for 5 years. My problem is that if the RPMs are gradually raised it's OK but open the throttle quickly and fire comes out of the carburettor. After running at idle for a while it will start popping out of the exhaust like it's loading up. Raising the RPMs up for a bit seems to clear it up and the vacuum gauge is steady at 20 but any quick wide open throttle from idle again will pop through the carb. It's loading up with way too much fuel. I can't understand it.
Chuck, Your problem is likely with the carburetor. Letting a Holley carb go dry for so long causes the gaskets inside to shrink and fail. Have the carb cleaned and rebuilt. That should turn your flame thrower into a tire burner instead.
Cold start problem - Cold start problem
Cold start problem
Dr. John I have a cold start problem and I've had it checked out and they can't find the problem. They think it's the EGR valve which is 100 pounds and I can't see replacing it for that much money with it only being a guess, what should I do?
I can't see why you would need the EGR valve replacing in the first place. The only way an EGR (Exhaust Gas Recirculation) valve could cause a cold start problem is if it was causing a warm running problem as well. The EGR valve remains closed while an engine is being started and in most vehicles does not function until the engine has warmed to a specified temperature. The best deal for you Art would be to get a second opinion.
In-Car Computer Question - In-Car Computer Question (Reset)
In-Car Computer Question
I would like to know if you have any opinions on dumping the computer by taking the positive and negative cables off the battery and touching them together for 20 seconds to clear the computer of any stored codes. If so, will a vehicle that's equipped with air bags, possibly deploy the air bag?
Actually Cecil, it's a common practice to disconnect both battery cables from the battery and not only hold them together but to connect them for the duration of the service being performed. For example when servicing the air bags some vehicles require the battery cables being joined for 15 minutes to a half hour before performing service or repairs that involve the air bag system.
It is not uncommon for todays vehicles to have several computers on-board. Inside the computers there are capacitors that will hold/store electrical energy. Connecting the battery cables provides a means of dissipating this stored energy without causing any harm. In most cases (not all vehicles) the software to operate the systems is not volatile and will be safely retained in the computer/s. If you have an anti-theft radio be sure you have the radio code so it can be reactivated.
Steering Wobble & Leaky Windscreen - Steering Wobble & Leaky Windscreen
Steering Wobble & Leaky Windscreen
Hi Doc, I thought you could tell me where to go on to get possible solutions to my problems. Problems are: 1. A wobble in my steering wheel from 0-25 mph. 2. A leak inside my car from the windscreen. I've had mechanics try to fix both and no luck.
Well Allison you don't have to go anywhere else the answer is right here, right now. A low speed wobble in a steering wheel is most often caused by tire problems. You may have a tire that is in the early stage of failure. This condition cannot be ignored!
As for the leaking windshield it's a no brainer. On most of today's vehicles the windshield is set into a self forming urethane seal that, once cured, becomes the sealing gasket between the windshield and the windshield frame of the vehicle. If the urethane seal does not fully contact the windshield and/or windshield frame of the vehicle, water can leak by. In some cases, additional sealer can be applied from the outside to seal the leak. Otherwise, the windshield will have to be removed to be re-sealed correctly.
To have the tires checked go to the experts, a tire outlet...............For the Windshield again go to an expert, an automotive glass company....you'll find both in your Yellow Pages, I am sure you have that book in the UK?
Service Light Always On - Service Light Always On
Service Light Always On
My service engine light was on for a week, I thought it was because I did not put the petrol cap on properly. I read in the manual it should take about 3 cycles for the light to go out. After a week the light was still on, so I took it to the dealership, they did a diagnostic test and said the 02 sensor skipped. They reset the computer so that the engine light went out. A week later, the engine light is back on, afterwards the battery light came on and shortly after that the ABS indicator light came on. As I was driving home the radio went out and the lights inside the car started to dim. After shutting the car off, I tried to restart and it wouldn't. The headlights did come on. I noticed as I put the security alarm on the car, it sounded weak. Could you please give me an indication of what may be wrong with this vehicle, so that I can trust, when I take it to the garage, I have some sort of idea what is going on with the vehicle.
It's very unlikely that the check engine light from the week before is related to the problem you're having now. From your description I would guess that the charging system on your vehicle has failed. The first indicator was the battery warning light. The job of the charging system is to provide electrical power for the vehicle's needs and replenish the battery. The main job of the battery is to store electrical power for starting the engine. After the engine is running the charging system takes over. In the event of a charging system failure the vehicle's electrical demands are supplied by the battery.
On todays vehicles it doesn't take long for the battery to drain to the point that other computer systems take notice. When they see that the power supply to them is too low to operate correctly the other computers start complaining which would explain your ABS warning light. As the battery gets lower the radio will drop out, which is just about the time the engine computer will start thinking about throwing in the towel. At this point the battery has about enough power to light some lights but wouldn't even think about cranking the engine over. The fix for your vehicle is likely a new alternator. Once you're up and going the check engine light may come back on because of the O2 sensor problem, but that won't kill the battery.
Plymouth - Buzzing noise when shifting into reverse
Plymouth
I hope you can help me, I have a Plymouth Sundance 1993 and have started to hear a buzzing noise every time I shift into reverse (automatic ). I thought at first it was the exhaust system, but I have checked this and nothing is loose at all underneath the car. Do you have an idea of what this could be it is driving me nuts!
Can I assume you have checked the baffles in the muffler (silencer)? This is one thing that can give off a buzzing sound if they come loose inside. There is also an inherent problem with the 41TE transmission on these vehicles, which have been known to give off this very sound. I suggest you let the specialists in an automotive transmission garage look at this, what is needed to stop the noise if it is the transmission is the valve body assembly and/or the valve body separator plate. Either or both of these would have to be replaced.
Saturn SL-2 - Air conditioner problem
Saturn SL-2
I own a '93 Saturn SL-2 with an air conditioner problem. The A/C gives cool, not cold air, and the garage said that the compressor needs to be replaced at the cost of 400 pounds. For a short-term fix, would juicing up the A/C with more Freon do anything to make it colder? Or will it never be cold again? Basically, if the compressor is shot, would I still be getting some cool air or is it a simpler problem?
Stewart, the A/C compressor is a mechanical pump. If the pump is weak adding additional refrigerant will not make a weak pump, pump any better. If adding more refrigerant does make the A/C system cooler then I would question the diagnosis, (does it really need a compressor?). A word of caution, if the A/C compressor is noisy "DO NOT!" operate the A/C system. Before an A/C compressor fully fails it can pump it’s insides into the rest of the A/C system. The cost to remove the debris from the rest of the system will make 400 pounds look like a deal. I would definitely get a second opinion from another A/C repair shop
Buick Century - Engine light problems
Buick Century
The service engine light will not go off in my 1998 Buick Century. I took it to the dealership and they said there is something wrong with the transmission. However, in the service manual it says that this light only refers to problems with the emission controls. Are they making this up? They want 400 pounds to look at the transmission and they couldn’t tell me exactly what they would be repairing.
Ron, The owner’s manual is not telling you the whole story. The Check Engine Light can come on with transmission problems as well. 400 pounds to look at a transmission and not be able to tell you what they are planning to repair is concerning to say the least. Someone has to have some idea of what’s going wrong or they wouldn’t be removing the transmission. The computer scan can’t always tell you what’s broken it can however point to possibilities, whereas a visual inspection can.
With this information and an understanding of the transmission operation a tech has a good idea where they’re going to look and what they might find once the transmission is disassembled. If they are not willing to spend some time with you and provide an explanation, then you should find a repair facility that is willing to. Certainly get one or two more estimates. You should have the scan results from the first place because you obviously paid for something. If you have these results take them with you to the other facilities.
Buick Century - Erratic temperature readout
Buick Century
I own a 98 Buick Century Limited with automatic climate control that has an outside temperature readout on the screen. Of late, this read out has been erratic, showing 20C when the outside temperature is freezing at 0C . Where is the sensor located? Can I replace it myself? Or, is that the problem? What can I do Doc?
Yes, you can replace it yourself Clive. It's actually located in front of the radiator air baffle on the right side just behind the front bumper. O-yes, you should know that the software/program for the temperature sensor does not update the display unless the vehicle is driven over 20 MPH for more than 3 minutes. If the vehicles speed drops below 20 MPH during the first 3 minutes the sensor display will not be updated. So if you take your vehicle out of a warm garage and do not get above 20 MPH within 3 minutes you may find that the readings are not updating correctly. You may want to check that out before you replace the sensor Clive
Buick Grand National - White exhaust smoke
Buick Grand National
Doctor John, I have an 86 Buick Grand National with a 3.8l SFI turbo engine. The engine runs fine, no oil or antifreeze usage. However, I get white smoke out of the exhaust particularly when I am decelerating. Compression is good, all sensors have been checked or replaced. Do you have any idea what the problem could be?
White smoke out the exhaust is a good indicator that your Grand National has a problem. I am going to suggest checking the turbo seals. Leaking turbo seals can introduce small amounts of oil that will create a noticeable exhaust cloud. That oil will turn white when it travels through the engine and out the exhaust. It does not take much oil to cause the smoke you're talking about. Have this job done ASAP as major damage can occur in quick time.
Cadillac Sedan Deville - Warning Lights
Cadillac Sedan Deville
I have a 1996 Cadillac Sedan Deville with 175,000 miles. Recently, I have been getting a service engine light and a service transmission message while driving along at highway speed. The only effect that I can determine is that I get a hard shift but the transmission works O.K. otherwise. The problem clears after a few days of driving then reappears. Only once has this occurred while the transmission was shifting. I cannot seem to find anyone who has experienced this problem before. Have you had this problem submitted to you and if so, what is the answer?
Juan, the transmission in your vehicle is computerized, and from your description the computer is not happy and wants some attention.
When the computer loses important information for operating the transmission a back-up program is then initiated. When this occurs the shifting becomes more pronounced (harsher), gas mileage will drop, both the check engine and 'service transmission soon' light will be turned on.
Many repair shops just do not deal with computerized transmission problems. Your best shot for a repair on your Caddy is to go the dealer or an automatic transmission shop that specializes in computerized transmissions.
Cherokee Sport 4.0L. automatic - Engine rattling sound
Cherokee Sport 4.0L. automatic
I have a '94 Cherokee Sport 4.0L. automatic. While engine is idling I hear a rattling sound from inside the engine. Has 126,000 miles on it and has been kept well with all the services done to date. When you increase the engine RPM the sound goes away, it's only at Idle. Could this be valves or rockers, or do you think there is anything to worry about?
Hi Tom, Have the bolts from the flex plate to the torque converter checked. I have heard this noise many, many times occurring in Jeeps equipped with automatic transmissions. Over time these bolts will loosen and the engine will develop a very disturbing noise that appears to be from the engine. It's most often pronounced at idle and with increased throttle movement. With the transmission in gear and under load, accelerating, the noise may not be present. In any case, these bolts have to only loosen a little to create some very strange engine type noises
Cherokee Sport 4.0L - Rattling sound
Cherokee Sport 4.0L
I have a 94 Cherokee Sport 4.0L. While the engine is ticking over I can hear a rattling sound coming from inside the engine. The vehicle has 126,000 miles on it and has been kept up with all the service to date. When you increase the engine RPM the sound goes away, it's only at tickover it happens. Could this be valves or tappets, or do you think there is anything to worry about?
I have had this question before and my answer will be the same Tom....Have the bolts from the flex plate to the torque
converter checked. We see this problem occurring in Jeeps equipped with automatic transmissions. Over time these bolts will loosen and the engine will develop a very disturbing noise that appears to be from the engine. It's most often pronounced at idle and with throttle movement. With the transmission in gear and under load, accelerating, the noise may not be present. In any case, these bolts have to only loosen a little to create some very strange engine type noises.
Chevelle - Brakes stay on
Chevelle
Dr. John, I imported a classic from the US last year and the problem I am having now is the brake calipers on my '70 Chevelle will not let the rotors turn by hand. I have installed a new master cylinder, new calipers, new brake lines and new pads. When I say "Turn by hand," I mean with the tyre mounted. it takes all I've got to move it. There must be something wrong because pads don't last very long 4000 miles or less?
Reggie, the reason the front brakes are staying on is due to residual pressure in the brake system. Now the question is why is this? If both disc brakes are dragging then the problem is likely with the master cylinder, even though it's new.
There are 3 possibilities.
1. Check the push rod from the brake pedal to the master cylinder. Some push rods are adjustable and the adjustment can change. If the adjustment is too tight the push rod can actually cause the brakes to drag in the manner you describe. The fix would be readjusting the push rod or, if not adjustable, adding shims to provide the correct clearance.
2. There are check valves used in master cylinders called residual check valves. The residual check valve is used "only" on drum type brakes. If a residual check valve is used on disc type brakes it will cause the brakes to drag. Your vehicle's brake system requires a residual check valve for the rear brake (if drum type) and no check valve for the disc brakes. If the master cylinder has a check valve in each port then it's the wrong master cylinder for your vehicle.
3. Human factor, be sure that the rear brake line didn't get crossed somehow with the front when fitting to the m/cylinder.
You didn't mention whether you changed flex brake hoses, if they weren't I would change them as well especially if they are originals. These can colapse internally and cause a similar problem though it usually happens on one side or the other. There is also one fitted at the rear axle.
Chevrolet 2000 - sounds like something is slipping on acceleration
Chevrolet 2000
Dr. John I am trying to analyse this problem. Hopefully you can help. I have a 2000 Chevrolet with a 5 speed. Recently when I accelerate, it sounds like something is slipping, then grabs and the car takes off. It seems to only do this in second gear and up. I can be going 20 or 80 MPH. I thought it was the clutch; however, if I am going down the highway and gradually accelerate the clutch is already engaged and should not be involved. Could this be the timing belt/chain?
Shari If a timing belt or chain slips in any engine there will be a notable loss of power, that will not return, or the engine will stop completely. From what you're describing I would be leaning towards a clutch problem.
Once a clutch starts slipping the problem can only get worse. Take a tech for a test drive for their opinion on
the problem. If it is the clutch starting to fail at least you can plan to have the vehicle repaired before it just stops moving.
Chevrolet - pressure loss problem - Is the transmission toast?
Chevrolet
One of my sons decided to take a short trip to town in his brother's 2001 Chevrolet. About a mile from home, the car stopped. He said the revs went up to about 4000 and it was only doing about 30 MPH just before it quit. When I got home I decided to check it out. I checked the A/T fluid, it was down about a quart. The car will not move, regardless of which gear it is in. The check engine light is on. It has 4 codes showing on the ALDL. Is the transmission toast?
Would you like peanut butter or jelly to go with that toasted transmission Carl? It doesn't sound good. There is a pressure loss problem and with those codes it's likely that it's more than just low fluid. You can check with a transmission shop but I've got a feeling that transmission is toasted and a rebuilt or replacement is in your future. Shop around for a good honest, reliable and trustworthy transmission shop though.
Chevrolet Impala - Leaking Sunroof (Newly Fitted)
Chevrolet Impala
I have a Chevrolet Impala and I have just had a sunroof added, now every time it rains I see water getting in the car, this is not supposed to happen is it? My friends tell me all sunroofs leak?
Of course all Sunroofs leak Jenny . That is, if they are installed incorrectly! So as your Sunroof is leaking get the car back to the installers ASAP and have them fix it right!Water leaking into the vehicle is going to cause untold problems!
Chevrolet Malibu - Clock spring is broken
Chevrolet Malibu
Doc, I own a '97 Chevrolet Malibu, I just found out that the clock spring is broken. I would like to know if there is any danger of the air bag going off on its own? And also is it possible to deactivate both air bags? How can it be done?
Joel, I will not be the one to tell someone how to bypass a safety device. Though there are concerns regarding air bags, from what I've seen at accidents they are an effective safety device. Like any safety device it does have to be used correctly. I have not heard of a failed clock spring causing an air bag to deploy. But the potential does exist if the wrong wires make contact. Clock spring is a name used to describe the winding of wires from the steering column to the steering wheel. These group of wires wind-up and unwind, much like a clock spring as the steering wheel is turned. Thus the name clock spring. My suggestion is to install a new clock spring. In the event of an accident I would want every bit of technology performing correctly. Being able to walk away is a good thing.
Chevrolet - Check Engine Light Problems
Chevrolet
Dear Dr. John, I have a 1998 Chevrolet my check engine light keeps flashing
on but not every day. Do you have any idea what would cause this, and what
I have to do about it?
Hi Ray,
Most times this first starts to happen on highway trips and 90% of the time this can be attributed to the O2 sensor(Oxygen sensor) but that's not to say it is always the main cause, most garages after they have performed a ' fault code review ' will get this code up with other codes and will change this first. The light may go out and come back on 2 days later. So there may be a miss-diagnosis here, and a waste of money for you. If this ever happens to you on future occasions always remember to ask for your parts back, they belong to you anyway. If there is a dispute over the problem remaining you have still retained the evidence that your 'old ' part most likely still works and wasn't the problem.
With the check light being on all the time there is no quick answer, more diagnosis needs to be done to determine the ' real ' cause. What this light does in coming on shows that input from one or more engine sensors is reading outside of its normal range, or that it has failed. This will trigger a malfunction circuit in the ECP ( engine control processor ).
The sensor may or may not be the primary cause. A failure or fault in other engine systems could create a condition that will cause a sensor to read out of range.
To really determine the cause of your problem. I would first have the check on the ECP for ' fault codes '. If there is none, I would suggest an analysis using a vehicle analyzer.
Chevy Blazer - CPI/fuel injector leaking fuel
Chevy Blazer
The CPI/fuel injector unit on my ‘93 Chevy Blazer is leaking fuel making the vehicle run rough and smell. I understand this is common with the 4.3 Vortec engine, is this so? The dealer wants 340 pounds for the part. Where can I buy an aftermarket part?
The problem you’re describing has been the black plague to many a GM owner. It is such a common problem that most GM suppliers stock over 80 of the fuel injection units at all times. Until recently, the only replacement part available was from GM. Now, there are aftermarket replacements available. But guess what? They’re GM units just in different boxes.
Surprisingly the pricing isn’t much different either. The troubling part is that the whole fuel injection unit doesn’t have to be replaced. The component that fails is the fuel pressure regulator. The pressure regulator has a diaphragm that cracks allowing unmetered fuel to enter the intake manifold.
The word out on the repair street is that a replacement pressure regulator is going to become available. When ? I don't have a clue. In the mean time, operating a vehicle with a failing pressure regulator is a good way to dramatically shorten the life of your vehicle’s engine. Yes I agree the replacement injection unit does hurt the bank balance, but it is cheaper than a replacement engine and a fuel injection unit.
Chevy Blazer - Accelerator pedal sticks
Chevy Blazer
The accelerator pedal in my '98 Chevy Blazer sticks. It only sticks immediately after starting the vehicle. After that it usually does not stick until the next time I start the vehicle. Do you have any suggestions to prevent this?
When you say the gas pedal is sticking do you mean just as you step on the gas pedal, that very first moment of movement? If that is the case it is likely that you have carbon deposits on the throttle plate and bore of the throttle body. The problem may even be more pronounced when the engine is cool.
The solution is a simple cleaning of the throttle plate and bore. Use a soft tooth brush and a spray bomb of fuel injection cleaner, similar to carburetor cleaner. Just make sure on the side of the can it's says, " for use on injected engines only " Add a liberal amount of elbow grease until the surfaces shine again and the problem should be gone.
Chevy Corvette - Short on the Air Bag circuit
Chevy Corvette
Doc! I’m having to deal with a short of some kind that is located on the Air Bag circuit of my ‘90 Chevy Corvette. I have eliminated all air bag connections except the main one from the DERM. If this connection is not made , the car will not run. The car will start and you can drive it about a quarter mile and it will blow the air bag fuse. I think there’s something else on this circuit that is really causing the problem, but I do not have an electrical schematic that details the air bag fuse circuit. Anyway , when the fuse blows, the engine cuts out. I put a new fuse in and it starts up , I go a short distance and it blows another fuse. Hope you can help.
Jamie the Air Bag fuse on you vehicle just happens to be tied in with the vehicle’s engine computer and a relay or two. After looking at the wiring diagrams for your Vette I could easily see that GM did not intend to make it easy for someone to disable their vehicle’s Air Bag system.
Here's a couple of items you should check for possible causes for fuse failure. The canister purge solenoid and the electric air pump relay; now both units are powered by the Air Bag fuse. A shorted electrical winding in either unit would cause the fuse to blow. The Diagnostic Energy Reserve Module (DERM) is not known for blowing fuses but it is possible. There is an isolation/diagnostic procedure of all the systems that the Air Bag fuse powers, but they should be performed, by a technician that is knowledgeable. Because if you jump the wrong wires, you’ll cause the costly vehicle’s computer to go as Cheek and Chong would say, ' Up in smoke ' Let the professionals look after it Jamie.
Chevy Lumina Van with a 3.4 DOHC - Engine makes a knocking type noise
Chevy Lumina Van with a 3.4 DOHC
Dear Doctor, I have a ‘96 Chevy Lumina Van with a 3.4 DOHC. My concern is that I have just tried out my A/C for the coming summer. When the A/C is on the engine makes a knocking type noise. This noise appears to be coming from inside the engine and goes away when the A/C is turned off. The engine's idle or driveability isn't affected by this knocking. So could this be the beginning of something bad?
Jason, I have no reason to believe that there is an engine problem. The first item I’d suggest checking would be the A/C compressor or the mounting bracket for the compressor for loose bolts. If either has loosened up, it doesn’t have to be by much, a knocking noise can occur when the A/C compressor is on. If the compressor and mount are tight then the A/C compressor itself would become suspect
Chevy Malibu - Stalling Problem
Chevy Malibu
Dr. John, I have a 1978 Chevy Malibu that is in great shape. My trouble is that in cold weather it starts okay, but at the first traffic light or any stop it stalls. I've tried letting the car warm up, but the same thing happens; it stalls at the first stop. My garage mechanic turned up the idle, but it made no difference. Any suggestions?
Because of your vehicle's age Ellie there could be several possibilities. For one example there is a device called a heat riser, used to quickly heat the intake manifold by diverting hot exhaust gases to a passage under the intake manifold.
Cold intake manifolds allow gasoline to separate from the air as it travels to the cylinder, resulting in puddles of raw gas settling on the bottom of the intake manifold. This can cause a stalling condition.
The heat riser valve could be sticking and/or the passages in the manifold plugged with carbon.
Have your technician "take the time" to go through proving and inspecting the different controls on your vehicle's engine. With over twenty years of operation there will be worn parts that just have to be replaced or serviced.
Good Luck Ellie!
Chevy Suburban - Glow Plugs
Chevy Suburban
I need to change the glow plugs in my '83 Chevy Suburban. Are there any special procedures or precautions that I should know before doing this?
Be sure to blow any debris away from the area of the glow plugs before removing. Anything falling into the glow plug port can be devastating to your engine and checkbook. If the glow plugs are rusted and refuse to turn, start the engine and try turning the glow plugs as the engine heats up. Always install a complete set; the controller relies on the glow plug's internal resistance to control operation. Before they're installed, lightly coat the threads with anti-seize and do not over tighten.
Chevy Impala - No vacuum
Chevy Impala
I have a '95 Chevy Impala and there is no vacuum from the vacuum port of the throttle body to the PCV valve. Any suggestions on what the problem is or repairs that are needed will be appreciated
The problem is likely due to a carbon build up, and this problem is not uncommon. The build up is caused by moisture, gasoline vapors, exhaust gas and other contaminates that normally form in the crankcase of an engine. The job of the Positive Crankcase Ventilation (PCV) valve is to remove these gasses and feed them back to the engine to be burned during combustion. As these gasses travel through the PCV system they condense, collect and build-up on the passage walls. Over time these deposits will become so great they will restrict or even block the vacuum passage in a carburetor or fuel injection throttle body. The fix requires removal of the throttle body, cleaning the passages and a new gasket.
chevy - Tyres Problem
chevy
Has anyone heard of a tube moving inside a tyre? I drive a 1955 chevy on stock rims, with 205x75r15 tubed whitewalls.
I was returning from a show recently, doing a steady 50 mph on a (luckily) straight deserted peice of road,when pow...offside front tyre failed. After bringing the car to a stop, I got out and inspected the damage. The valve was nowhere to beseen. I took the tyre and rim to a reputable tyre shop. The tyre was removed and thoroughly inspected. No foreign objectdamage was found, and it was evident that the valve had sheared off at the base, resulting in instant deflation. The tyre hadbeen on the car for approx. 2500 miles. A new tube was fitted, and pumped up to recommended 24 psi. This all occuredabout 2 weeks ago. Upon checking the tyres today, prior to a run out, the new tube on the same tyre, appears to havemoved slightly in relation to the hub cap. Is the hub cap moving, or have I got a dud tyre or rim? It is quite frustrating, and I really don't want to repeat the experience of another blowout.Hoping you can help, Regards Gus Turney.
Hi Gus! Sorry for the delay in replying, but I was at my summer condo in Florida for a much earned vacation.
You were lucky as normally when a radial is run flat for a minimum of 50 feet the rim just cuts right into the tire, ruining it for good! As for the tube problem on your vehicle, there are a few things that can happen here. 1) It's the tire that is moving around the rim, not the tube, but it will of course pull the tube with it thereby shearing off the valve. 2) The wheel disc will also cause this too, mostly on discs which are fitted with separate clips. If your discs have the grippers all the way around, try bending them out a bit with flat nosed pliers and then banging them back on with a rubber mallet!
As for the air pressures on the tires I suppose you are going by the sticker in the glove box at 24 psi? This is wrong for your vehicle as this low pressure is causing a tremendous amount of heat build-up in the tire and helps in causing the tire to move around the rim. All your four tires should be running at 35 psi, you get less heat build-up, less friction heat, and better gas mileage...............Plus because the tires are under-inflated your tires would wear prematurely on the inside and outside, but be fine in the middle.
If you look at the psi rating on the side of the tire, it will show the maximum pressure you can inflate to. Most radials show a spec for either 32 to 35 psi. My vehicle is a 1957 with radials and the manufacturer told me to run them at max. This wont cause any problems as when air is heated, as you no doubt know, expands 3 or 4 lbs. over this spec. The tire is made to accommodate this.
Now one last thing for you to check, whoever recommended 24 psi for this tube is wrong. I just hope when you fitted radial tires on your Chevy you had them install radial tubes as well? You must have these as the original bias ply type are not suitable for radials.
Let me know on these questions I have asked, or if you have any more questions don't hesitate to e-mail me in the future. Again I apologize for not being able to answer your question immediately. Can you send me a picture of your car, I am always interested in seeing members vehicles
Chevy Malibu - Cold weather, Stalling
Chevy Malibu
I have a 1978 Chevy Malibu that is in great shape. My trouble is that in now in the cold weather it starts okay, but at the first stop I make it stalls. I've tried letting the car warm up, but the same thing happens; it stalls at the first stop. My garage mechanic turned up the idle, but it made no difference. Any suggestions?
Gerry, Because of your vehicle's age there could be several possibilities. For example there is a device called a heat riser, used to quickly heat the intake manifold by diverting hot exhaust gases to a passage under the intake manifold. Cold intake manifolds allow gasoline to separate from the air as it travels to the cylinder, resulting in puddles of raw gas setting on the bottom of the intake manifold. This can cause a stalling condition.
The heat riser valve could be sticking and/or the passages in the manifold plugged with carbon.
Have your mechanic "take the time" to go through proving and inspecting the different controls on your vehicle's engine. With over twenty years of operation there will be worn parts that just have to be replaced or serviced.
Chevy Venture - Warning lights
Chevy Venture
Doc I have an 2001 Chevy Venture, With ABS & Traction Control.
Both the ABS & Traction Control warning lights came on at the same time and stay on.
Are these systems interconnected? In your opinion what might I expect from the dealer for after
warranty repair service on a '01 Chevy Venture with 51,000 miles? Everything seems to be working okay at this time.
It wouldn't hurt to ask the dealer if there is something that they can do for you. But, if the vehicle is out of warranty don't get bent all out of shape if they say no. The ABS system and the Traction Control system both use many of the same input sensors to operate. If a jointly shared sensor fails both warning lights will turn on. For the cause of the joint failure to be known all that has to be done is ask the system computer. As a rule it will gladly share the information to guide you to a repair. I'll bet a coffee that you'll have a wheel speed sensor failure. This has been the most common problem that we've seen on these vehicles. So ask the technician to do a scan for you.
Chevy C1500 - Diagnostic trouble codes
Chevy C1500
Hi, I have a 1996 Chevy C1500 with a 4.3l engine. I was wondering if there is a way for me to pull the codes through the connector? I have heard that you can jump 2 of the plugs but I wasn't sure which ones or if that was true. If you could let me know that would be great!
Allen, Once upon a time you could use a jumper to get the vehicle's computer to blink/flash the check engine light to retrieve diagnostic trouble codes.
Well, I am sorry but you just can't do that any more. You'll need some sort of code reader or scan-tool to get that information from your vehicle's computer.
About the only thing you can do with the new diagnostic systems connectors is blow fuses, damage system components, retrieve anti-lock brake diagnostic codes (warning only on some systems) and in general cause more trouble for yourself than you can image. So let the experts do the 'Fault Code Review ' for you
Chevy Beretta, Stalling - 90 Chevy Beretta, Stalling
Chevy Beretta, Stalling
I have a '90 Beretta V6 MFI that is stalling while driving down the road or while going uphill. I can duplicate the problem if I sit in park and hold the throttle at 3000 RPM; the car will eventually die. I checked the fuel pressure and it was reading to spec. I replaced the fuel filter and checked for codes, but there weren't any. Once the car dies I am unable to restart it for quite some time, however if I lightly tap on any point of the throttle body I am able to start the car with no problem. I'm terribly confused because if there was a problem, wouldn't I get a code? Please help
A vehicle of this age can be having a TDT (Total Driveability Tantrum) and still not turn a ' Check Engine Light ' on or set a computer code. What is intriguing is the way that you can duplicate the problem. Now was the fuel pressure being monitored while the problem was occurring? If the fuel pressure is good and there is good ignition spark, I can't help but wonder if there is a problem with the vehicle's converter or if there is a restriction in the exhaust. I have seen some strange driveability problems with similarities to yours caused by failing catalytic converters.
You can run a check on the catalytic converter very easily with a vacuum gauge, takes about 2 minutes to tell you whether you have a partially restricted Cat.
As for the engine starting after tapping on the throttle body, that must be one special wrench you have, I bet you bought it from Harry Potter didn't you?
Chevy Tahoe - Something constantly running
Chevy Tahoe
Underneath my '01 Chevy Tahoe I heard something constantly running just under the driver seat on the frame. I needed to stop it and found that when I removed the 60 amp ABS fuse it would turn it off. When I put the fuse back in, it would run again.
From your description it sounds as if the Antilock Brake System's pump is not turning off. The ABS has a computer called an Electronic Brake Control Module (EBCM). When you remove the 60 AMP ABS fuse, you're removing the power supply from the EBCM. The EBCM just happens to control the ABS pump. If the ignition key is in the off position and the ABS pump is still running it is likely that the computer 'EBCM' that commands the pump's operation has an internal electrical problem. Have a qualified technician inspect and perform a computer check of the ABS computer. In the event that the EBCM is the cause for the problem, it is replaced as an assembly. The assembly includes the computer, pump, control valves for the ABS system and is a pricey unit. The ABS pump is not designed to be running all of the time and will eventually fail. Once the pump fails the ABS system will be inoperable.
Chevy Silverado 1500 - Blowback in the air intake
Chevy Silverado 1500
I run my Chevy Silverado 1500 with a 4.3 engine on propane. The engine sometimes gets blowback in the air intake. The last time it damaged the air intake. I have heard this can be a common fault on some propane conversions. What can I do to stop this?
That is a problem on many newer vehicles that are converted to operate on propane. Part of the problem has to do with the new style intake manifold designs. The newer manifolds have long passages called runners that the air entering the engine travels through. Also the newer style intake manifolds are designed to manage/optimize air flow to the engine. The fuel injectors introduce fuel just as air enters the cylinders. With propane, it is mixed with the air as it enters the intake manifold. With long paths for the air and propane to travel you have created the near perfect conditions for a lean backfire as the throttle is first opened. When this happens it can ignite the air & propane as it enters the intake manifold.
This creates a propane torch, which does great things to the plastic and aluminum used in todays intake manifolds. If this condition is a common event on your vehicle then something isn't installed correctly; you have ignition, fuel control or engine problems. A tech working on these systems has to know his/her stuff to rid your truck of this problem. A lot of people install these systems, but it is few and very far between that know how to optimize their operation. Once the system's working right it's better than gas, real clean and the engines go/last longer.
Chevy Cavalier misfires - Chevy Cavalier misfires
Chevy Cavalier misfires
I've read a few of your tips regarding Chevy Cavalier misfires In one I read that it is probably plugs or plug wires, which I have replaced. People suggested to me to take it to a technician instead of trying to solve it myself. So I go to a tech who finds that there is a single cylinder misfire code, but no other diagnostic codes.
When it rains, the car starts to miss (under load) and occasionally you can hear an audible backfire in the engine compartment. The check engine light flashes a couple times then it stays on and the ETS (Electronic Traction control) light stays on. The only diagnostic response is a misfire. I've replaced the coil pack, plugs and wires.
Is there something with a traction/wheel speed sensor that is triggering a misfire for traction related purposes? Maybe the ignition is fine and something else is telling it to misfire!? Any thoughts Doc?
Thomas, Let me take a moment and explain why the electronic traction control which is called Enhanced Traction System (ETS) warning light will turn on when the engine computer sees a problem. The ETS system monitors wheel speed via the Anti-lock Brake System (ABS). If the ETS system sees a wheel spinning due to snow, ice, rain etc., the ETS computer sends a request to the vehicle's engine computer to reduce torque. The engine computer responds with a combination of strategies.
In the engine computer's bag of tricks to stop wheel spin it can perform any one or combination of the following; cut fuel off by trimming or turning off fuel injectors, retard the spark timing or up shift the transmission. In the days of old we just let up on the gas pedal. Now the computer does it for you. If you have an engine running problem it is more of a problem than you realize. The engine computer is the high command center. The engine computer will work and respond to information from the other computers in the vehicle. But in the event there is a system or running problem that the engine computer is responsible for, 'it will' lock out all of the other vehicle computers.
If there is an engine running problem that causes the engine computer to store a code and turn on the 'Check Engine' light guess what computer doesn't talk to the others? The engine computer. The ETS computer gets upset when this occurs and turns its warning light on in protest. So, there you have it Thomas. If the check engine light is on the ETS warning light will come on as well and the ETS system will not operate until the engine computer problem is corrected.
If your vehicle is misfiring in wet weather you have to find the cause for the misfire. I'll bet you a pint of DD you have an ignition problem. In the shop we'll use a water hose, a mix of anti-freeze and water in a spray bottle or even a mix of salt and water in a spray bottle. The ignition system will get sprayed down and the spark leak hunt will begin. When you fix your misfire problem you'll turn the ETS light off too.
Chev Day Van - Lighting Problems/ Burn out
Chev Day Van
Doc, Can you help me troubleshoot my problem. A few days ago I lost the back lights in my Chev Day Van. I thought I could smell something burning. Also the dash lights are out. I checked the fuse and it was blown. I replaced it with a new 15 amp fuse and it blue right away. I went to 20 then 30, both burnt. I bypassed the fuse and started getting smoke (not too smart, eh). My brake lights work, my signals work, but not my emergency or back lights. I would appreciate any constructive advice rather than the obvious of going to see a mechanic.
Ooh Wee! Bypassing the fuse with a jumper is a sure fire ( excuse the pun ) way to get things smoking. You're likely to do more damage than good using that approach to identify the problem. Whenever a sudden electrical problem appears, the first question I ask is: what has been worked on recently? Has there been any body work or accessory upgrades such as a radio? A wire can be damaged during these procedures and become a problem a short time later. If I'm not mistaken you have problems with three different electrical circuits.
The dash lights use a different fuse than the tail lights and the emergency flasher is another circuit in itself. The ideal approach would be to obtain a wiring diagram and start tracing the wires from the fuse panel to the first connector and disconnect it, then install a new fuse. If the fuse doesn't fail then you know that part of the wiring is good. Then move to the next wiring harness connector of that circuit and repeat the procedure. A good wiring diagram, patience and time is needed to diagnose a problem like yours. If you still come up short, take your car to a qualified tech.
Chevy Malibu - Overheating
Chevy Malibu
My '90 Chevy Malibu won't stop overheating. I have replaced the water pump and thermostat. I've corrected the engine timing and put on a new timing belt. I have replaced the radiator, the car has not lost any power and there is no water found in the oil. The car will tick over for hours without overheating, but as soon as you're on the road and accelerating, the engine overheats within 2 to 4 minutes. Any ideas on what else to check? The local dealerships and garages are stumped and frankly so am I.
I don't mean to be the bearer of bad news Reg, but you have either a headgasket problem or a crack in a cylinder head. You've covered the bases. For an engine to heat that quickly under load there is combustion gases entering the cooling system. Here are a couple of tests you can try.
There is a chemical test ( dye ) for the cooling system that detects the presence of CO2. This chemical test is really good at proving that there are combustion gases entering the cooling system. To pin down which cylinder is the problem remove all the spark plugs ( mark which cylinder they came out of, then examine the firing end of each plug to see if there is any indication of that cylinder having coolant coming in. Most times the plug end will be washed totally clean in stark contrast to the others.
If the plugs all prove to be fine leave the plugs out and pressurize the cooling system while the engine is hot using a manual pressure pump with air gauge. If it is the garage (then they can perform the test.) If and when the pressure gauge shows it is leaking down then keep pumping it up each time over as long a period as you can.
At the end of the test period crank the engine over. If there is a problem you'll see coolant splashing out of one of the spark plug holes.
Chevy Silverado - Bumping Through Steering Wheel
Chevy Silverado
Dr. John, I own a 2000 Chevy Silverado with a bumping which I can feel in the steering wheel only when I turn right. This is the second time it's happened. The first time the GM here in England performed a lube of the steering shaft as per a TSB and it solved the problem temporarily, but now it's back. What's causing the bump? Is there more to it than a lube job?
The problem you're describing has been around for a while on GM, Chevy, Cadillac and Hummer H2 trucks. The intermediate shaft between the steering column and box seems to be clunking and is most notable when turning at low speeds and on rough roads. GM has been removing the intermediate shaft and packing it with grease. Some of our customers have found this to be the fix and some others (including you) have found it to be only a temporary fix. I would suggest going back to the dealer to have the problem addressed once again. At this time I'm not aware of replacement parts to correct this problem, but if enough customers keep complaining GM will likely have to step up to the plate will a real fix.
Chevy blazer - Multiple oil leaks
Chevy blazer
My 84 Chevy blazer with 160,000 + miles had severe multiple
oil leaks. I had a garage do a fluorescent dye check on the engine. After the dye check was done, the leaks stopped! Engine oil usage went from 1 gallon of oil per 600 miles to just 1/2 gallon for over over 2000 miles. Can these fluorescent dyes cause oil passage blockage? I'm worried that if this dye did seal these leaks that it could cause oil passage blockage.
Wow that's impressive Jim! I can't say that the dye check chemical was responsible for the reduction in oil consumption. The product is made for
finding leaks not sealing them. While the garage was checking your engine for oil leaks, did they service the PCV system? A faulty PCV system can cause a variety of oil leaks and be responsible for a high level of oil consumption. Either way, the dye check products that I'm familiar with, would not in any way restrict oil passages inside the engine.
Chevy Blazer - 98 Chevy Blazer temperature high
Chevy Blazer
My 98 Chevy Blazer temperature gauge got pretty high, all of a sudden. Then the temperature gauge dropped all the way down. Then the service engine soon light came on and the engine ran funny but the temperature gauge went up again. Also, at stop lights or other stops the temperature would rise and go into the red easily. But, when the RPMs went up the temperature would drop again? What is wrong?
I can't tell you what is wrong, but there are some checks you should perform. First, be sure the coolant is at the correct level. Don't just look at the level indicated on the coolant recovery tank. With the engine cool remove the radiator cap and check the level. A system problem can leave the coolant recovery tank level looking great, while the radiator is low. If the cooling system is at the correct level then you need to get into the vehicle's computer to see what is happening. The coolant temperature sensor for the computer is also used for the temperature display on the dash. If the coolant temperature sensor is failing, it will cause rapid gauge fluctuation and cause the service engine soon light to be turned on. By monitoring the coolant temperature sensor movement and comparing it to the coolant temperature at the radiator you can determine if the sensor is providing a true reading of engine coolant temperature. Also while your at it why not have a dye test on the coolant, just to make sure you haven't gotten a start of a head gasket leak, the dye will record if there is any Hydro Carbon or Carbon Monoxide fumes in the coolant.
Chevy Blazer - Leaking oil
Chevy Blazer
My 98 Chevy Blazer leaks oil. The dealer says the filter is loose, Duh!? Looks like the oil lines going to the oil filter adapter, block, radiator are weeping. Is this a common problem?
Replace those weeping oil cooler/filter lines ASAP! When oil starts leaking from the area of the crimp that clamps the flexible hose to the aluminum oil lines it is the early warning signs of failure. When the failure occurs it is without warning! What Happens? The flexible line blows off the aluminum tubing. The result is an oil leak so big that you have at best a minute to notice failure and shut the engine down without causing damage! Do not tempt fate for your check book may lose. Have the oil cooler/filter lines replaced! Oh! Also change your dealership the guy hasn't a clue, bet he didn't even look at the problem.
Chevy Silverado - Blown manifold gasket
Chevy Silverado
The intake manifold gasket failed in my '96 Chevy Silverado. What caused the leak? Was it the incompatibility of the Dex-Cool anti-freeze and the gasket or mixing the red Dex-Cool antifreeze with normal green antifreeze?
First Brad, you should never mix the GM type red/orange colored antifreeze Dex-Cool with the green anti-freeze that most people are familiar with. The green anti-freeze will cause the red/orange Dex-Cool to degrade and not perform as designed. Now there are some concerns that you should be aware of. We have found that Dex-Cool, which is rated for 5 years or 100k miles, is not always making it to the 5 yr. or 100,000m mark. This coolant can go bad and when it does it gets real nasty and creates a pile of problems. I guess what I'm saying is do not be lolled in to believing that service is not required. Regular testing and inspection of the cooling system with Dex-Cool is a must.
As we all know, what works great in the lab often has contrasting results in the real world. Throughout the profession this stuff is known as ' Deathcool! ' I have had so many similar questions where others have had problems especially with low mileage vehicles having to replace radiators, water pumps, thermostats and the plastic intake manifold gaskets which get eaten away with Decool. In changing to normal anti-freeze consumers have had to have anywhere between 4 and 6 system flushes to get rid of the Dexcool.
Chevy Caprice - Idle speed be adjustment
Chevy Caprice
Doc, Can idle speed be adjusted on my '96 Chevy Caprice with a 6 cylinder? Frequently at idle, the power steering assist is poor and the Low Battery Voltage light comes on. When engine speed is increased with the accelerator pedal, both problems are corrected. I understand idle speed is controlled by a computer and may not be adjustable. I would very much appreciate comments.
Richie, I don't think there is a vehicle made today that doesn't have a computer controlled idle speed. In saying that, there is what is called a base idle speed setting. Tech's often refer to base idle speed as minimum idle air settings. The procedure for setting minimum idle air varies from vehicle to vehicle manufacturer. The procedure in most cases calls for adjusting the position of the throttle plates with what most people would call an idle screw.
Now a word of caution. The minimum idle air setting is a baseline for the computer to operate from. If the computer is not turning the idle speed up as you think it should be there may be a different problem.
The control of air speed above the minimum setting is the result of the computer actuating an idle air control motor. I would suggest having a scan tool plugged into your vehicle's computer and have your technician check (in GM vehicles) the idle air count.
The idle air count is the computer reporting what position the idle air control motor is being commanded to open. With this information the tech can then determine if there is a problem with the operation of the idle air control motor, or if other service is needed. Word of warning, if you just go in and turn what is perceived as the idle speed screw you can really alter the computer's response, creating a variety of driveabilty problems. If in doubt, let the experts deal with it.
Chevy - 2001 Chevy needs a new Body Control Module
Chevy
My 2001 Chevy needs a new Body Control Module (BCM). Some of my dashboard gauges work sparingly. I have had it diagnosed at the dealer I purchased it from as well as a reputable garage and both have confirmed the need for a new BCM. I was quoted over 400 pounds in both places. Yesterday the odometer froze. Is the BCM or engine control unit still tracking my mileage, and just not relaying to the dash or is it completely frozen?
Where is the BCM located? How difficult is it to replace at home?
You'll be pleased to know Matt the Body Control Module (BCM) is a breeze to replace. The BCM is located on the top of the glove box on your Saturn and requires few tools to remove and install. Hoewever, there is a BUT to this one.The BCM has to be programmed or it will not work. The only people that can program the BCM are the ones with the costly tools - dealerships. It's the BCM programming of it that is the biggest part of the job, money wise that is. The labor to remove and replace it is the easy part. As for what is happening with the mileage? It is hard to say. The BCM is what stores and reports the mileage information. The dealership tech can probably answer that when he/she is doing the job for you.
Chevy Silverado - Bumping through steering wheel on Right turn
Chevy Silverado
I own a 2000 Chevy Silverado with a bumping which I can feel in the steering wheel only when I turn right. This is the second time it's happened. The first time my dealer performed a lube of the steering shaft as per a TSB and it solved the problem temporarily, but now it's back. What's causing the bump? Is there more to it than a lube job?
The problem you're describing Mike has been around for a while on GM, Chevy, Cadillac and Hummer H2 trucks. The intermediate shaft between the steering column and box seems to be clunking and is most notable when turning at low speeds and on rough roads.
GM has been removing the intermediate shaft and packing it with grease. Some of our customers have found this to be the fix and some others (including you) have found it to be only a temporary fix. I would suggest going back to the dealer to have the problem addressed once again. At this time I'm not aware of replacement parts to correct this problem, but if enough customers keep complaining GM will likely have to step up to the plate will a real fix.
Chevy Trailblazer - 2003 Chevy Trailblazer & a musty smell
Chevy Trailblazer
I have an 2003 Chevy Trailblazer. When the vehicle is first started up, and usually in warmer weather, there is a musty smell coming from the ventilation system. I had already taken the vehicle in for this problem and they put a kit on it that cycles the fan for about 10 seconds at 15 minute intervals. My question is, is there a cabin filter on this vehicle or is there a better solution to this problem? Other than that, I like my Trailblazer.
Your 2003 Chevy Trailblazer is not equipped with a cabin air filter system. The Trailblazer's seem to be suffering from an odor (microbial growth) problem that is the result of water retention problem in the A/C system. The modification that was installed in the vehicle is designed to operate the blower motor (when deemed necessary by a little computer) for 10 seconds every 10 minutes up to 2 hours after the vehicle is turned off. The reasoning of this is to dry out the A/C unit of any water that has collected. Also, GM has a coating to spray on the A/C evaporator's cooling fins to help kill and prevent the swamp growth that is occurring. We've had some reasonable success with the aftermarket treatments. But, depending on the weather it has to be applied annually, if not more often. At this time I'm not aware of any real fixes for the problem.
Chevy Malibu Bonnet Release - Bonnet is stuck closed
Chevy Malibu Bonnet Release
How can you "unstick" a bonnet release cable on an "2000 Chevy Malibu? I can't open the bonnet to get my oil changed. It seems stripped!
That's no fun Sandy. Okay opening a hood of a vehicle that has a broken or stuck cable or even worse is a rusted or broken latch requires creative repairs. There is no book time and there is not a book out there that tells you how to do it. When such events show up in our shop it is just a puzzle to be solved. On some vehicles you can sneak in through the front grill and grab a part of the hood cable. Sometimes you have to unbolt the latch. That occurs after maybe the grill has been removed or the tech is working from under the vehicle. Sorry I have no easy answer here; it is just one of those jobs you have to work at.
Chevy Cavalier - misfiring when damp conditions
Chevy Cavalier
My 95 Chevy Cavalier has a problem when it's damp outside, it seems like it's misfiring. I was wondering if you had any idea what would cause that to happen.
The solution to your wet weather misfiring problem should be easy to correct. From your description, it sounds as if the there is a spark plug wire that is starting to fail (as in leaking spark). The largest part of a spark plug wire (about 90%) is insulation to keep the spark (electricity) contained and heading in the right direction. The under hood environment of any vehicle is harsh. From the day the engine first starts, the insulation of the spark plug wires are under attack from this environment. As time goes on the insulation degrades or is damaged. The spark (electricity) is always looking for a shortcut and once the insulation of the spark plug wire degrades enough, the spark will find a new path. A fine mist of water is just the needed ingredient to allow the spark to travel a different direction, other than to the spark plug, on a marginal spark plug wire. A new spark plug wire set should be the fix Michelle
Chevy 1500 - Electrical Problem
Chevy 1500
Doc, Great show, I listen every week that I can to your informative show, now it's my turn to e-mail you. My question is my son has a Chevy 1500, he attempted to hook up under dash lights without disconnecting the negative cable at the battery. On trying to start the vehicle it wouldn't start and I'm at a loss as to what may have shorted out, any suggestions on where to start looking?
I would start by inspecting the fuse panel/box. Hopefully, a fuse did its job and prevented a wiring harness melt down. If the fuses check good then go back under the dash, remove the under dash lighting and check the wires that your son spliced into. He may have gone into wires that carry signal and the load of the lighting system is getting in the way. When all else fails return the vehicle back to the original configuration and start over until you know just what wires your son is cutting into.
Chrysler day van - Dodgy Dealer!
Chrysler day van
Doc, I recently purchased a '98 Chrysler day van from a used car lot. The Check Engine light went on, owner's manual says, 'take it to an authorized dealer' of which I agree. The wheeler/dealer of course, had a different opinion. Told me to take it to *&* Garage. Did this twice, now the car doesn't run at all. Got Automobile Association to tow me to nearest Chrysler dealer where the car has now been sitting for 6 weeks. I'm trying to convince all involved that it is critical that this vehicle gets a professionally trained diesel mechanic for repairs. I did have Chrysler do the diagnostics and it is the injector pump as well as a glow plug and three other issues. Please shed your light on this issue. If I let the dealer service manager put his hands on it (he's not even a mechanic, let alone a diesel mechanic.) It would be like sending my van to the butcher shop? I'm not sure who can help in this issue. I suppose a solicitor is my next move. Wrong is wrong.
A car that is not running at all after being in the shop is a pretty scary item. Mr. wheeler/dealer put himself in a not so good position. But, I confess that I'm really confused about the Chrysler Dealership. The Chrysler Dealership should have at least one factory trained diesel technician on hand to service your vehicle. Or do you mean the wheeler/dealer wants to fix your vehicle. If the wheeler/dealer wants to perform the repairs (and the vehicle is under warrenty as in no cost to you) than you need to let that repair happen unless you choose to pay for the repairs yourself. In that case you can have anyone you wish to perform the repairs. Also realize that Mr. wheeler/dealer is responsible for the repairs he performs. If they are not correct or result in damage he bears a burden. Be sure to document everything well and it may not be a bad thing to check with your equivilent of our Better Business Bureau or a solicitor on your rights as a consumer. You could first try talking to your wheeler/dealer and see if he'll agree to a diesel mechanic checking it out and repairing it and Mr. wheeler/dealer would foot the bill. Nothing ventured, nothing gained I say.
Chrysler Sebring Coupe - Wheeel baringsnot lasting long
Chrysler Sebring Coupe
Dr. John, I own a '95 Chrysler Sebring Coupe with disc brakes. I seem to be going through wheel bearings like there is no tomorrow. I just had the passenger side replaced in November and now both front ones are gone. Did I buy a vehicle that was in a serious accident? I religiously get it adjusted for alignment every 4-6 months. Is the frame twisted? Why do my brake rotors keep warping? I live in the city, is it my driving style? I do not ride the brakes, I just drive like a sane man. I just had the rotors and pads replaced last January and now the 'ol pulsation is back. There is no ABS on this car. Please help me with this Lemon, parts are not cheap!
First I think you're wasting money. Why? An alignment every 4 to 6 months is a little too religious for me. I would not suggest alignments that often unless the vehicle was operating under conditions that required it. Wheel bearings, once in a great while we'll have a problem, but nothing to the extent that you're describing. The wheel bearing in your vehicle has an axle that passes through with a large nut to secure it. The quickest way to shorten a wheel bearing's life is to tighten that axle nut with an air tool. Hand tightening and torquing is the only way to perform the job. The impacting action of the air wrench will chip the bearing to roller surface. In a short time the chips turn into chunks and the wheel bearing is ready for recycling. If the same air tool is being used to tighten the lug/wheel nuts, then the brake rotors will quickly pass away to pulsation. The short of it? Too many problems with the same product? I would question the installation first Paul.
Chrysler Concorde - Very strong petrol smell
Chrysler Concorde
I am fairly savy when it comes to automotive repair, but this issue has me stumped on my 93 Chrysler Concorde. I have been experiencing a very strong petrol smell when driving the car. I tracked down, what I thought the problem was, and found a rubber hose off the PVC valve that had been totally eaten away by the petrol and oil. At the dealer parts counter I was informed that, Oh yeah, Chrysler did not make this hose out of petrol resistant rubber and that this is a common problem.
I replaced the hose with another potential defective hose, and thought the petrol smell would go away. Now I am having the smell continuing and have been able to isolate it, by smell, to the right side fuel injector while facing the car. The problem is the smell is intermittent now, where as before it was consistent, but when it does come on it is very strong to the point of getting a headache. I have tried to find the source but there is no outward indications of wetness or leaks. I was hoping that this was a known issue with a fix but my searching has been fruitless. Any help or suggestions will be greatly appreciated!
First, you should take your vehicle to the dealer and have it checked for a safety recall. My Information Systems shows Safety Recall # 790 addressing a problem with the fuel rail to the fuel injectors leaking. This covers Chrysler vehicles manufactured between '93 and '97that are affected by this recall. Your vehicle model and year is mentioned in this recall. Gas leaks in the engine compartment are not something to mess around with. The chance of fire is too great! If I'm not mistaken you may even be able to call the dealer with your vehicle identification number to confirm that it is part of the safety recall. Work performed for a safety recall is at no cost to the vehicle owner even if you are not the original owner of the vehicle. Use your vehicle savvy; don't wait in getting your gas leak diagnosed and repaired, do it ASAP!
Chrysler - Petrol flooding
Chrysler
Would you explain what could be reasons for petrol flooding an engine and how to start the car if flooding has occurred? I have a 1997 Chrysler
Larry, a flooded engine is an engine that has received too much gas for the amount of oxygen available for combustion. When this condition occurs the inside of the cylinders, as well as the spark plugs, will become wet with gasoline. A cylinder wet with gas will result in a reduction of cylinder compression, loss of lubrication to the piston and rings and cause spark to the spark plug to be misdirected.
Because the large majority of engines on the road today are fuel injected we'll cover how to start them if flooded. The computer has a program in it that is called the Clear Flood Mode. For the computer to activate the Clear Flood Mode it needs to see information that is out of the norm. This abnormal information is the sensor on the throttle reporting to the computer that the throttle is being held wide open, along with a crank signal to the starter.
This combo of information causes the computer to respond by reducing, and in some cases completely shutting off, the fuel injectors. This process allows air only to enter the cylinder and dry out the abundance of gas. As the correct balance of air and fuel return you will feel the engine start to fire at which point the throttle can be released and the computer will return to normal fuel delivery.
Chrysler New Yorker - What controls the air conditioner
Chrysler New Yorker
What actually controls the air conditioner to cycle on and off on an 88 Chrysler New Yorker with the climate control heating and cooling system? How would you diagnose a problem with this system when the compressor is not cycling, assuming there is adequate freon and proper voltage going through the compressor and pressure switch?
What actually controls the air conditioner to cycle on and off on an 88 Chrysler New Yorker with the climate control heating and cooling system? How would you diagnose a problem with this system when the compressor is not cycling, assuming there is adequate freon and proper voltage going through the compressor and pressure switch?
Chrysler - Lights coming on all over the place!
Chrysler
I have a 2000 Chrysler with a standard transmission. Whenever I press the brake pedal, not only do the brake lights light up but also the dashboard lights and outside winkers. When the headlights are on and I'm not pressing the brake pedal, the little turn indicators in the dash glow faintly. I've checked the fuses, all the bulbs and I'm at a loss.
This is really frustrating! Any ideas would be greatly appreciated.
I have a 2000 Chrysler with a standard transmission. Whenever I press the brake pedal, not only do the brake lights light up but also the dashboard lights and outside winkers. When the headlights are on and I'm not pressing the brake pedal, the little turn indicators in the dash glow faintly. I've checked the fuses, all the bulbs and I'm at a loss.
This is really frustrating! Any ideas would be greatly appreciated.
Chrysler Town & Country - Multiple Cylinder Misfire code
Chrysler Town & Country
Doctor John, My wife's 96 Chrysler Town & Country gave a P0300 Multiple Cylinder Misfire code. The first time this happened we towed it home. When the car arrived home, it cranked up and drove normally as if nothing had happened. As a precaution I changed the spark plug cables, spark plugs, and the MAP sensor, after 2-3 weeks same thing. We're afraid to bring the car to a Dealer or mechanic shop because of the way those people crank up the bills it is hard to deal with and asking for bankruptcy. Why aren't there any books that can tell you exactly what to change when a certain diagnostic code shows up? What is the best we can do to make this P0300 code disappear forever?
First, there is no exact repair or parts replacement procedure for a multiple misfire code. Too many factors can cause that code to set. That is why the repair/diagnostic procedure has the technician perform several tests to determine the needed repair. To make matters worse, your vehicle only exhibits the condition/problem once every 2 to 3 weeks. From the diagnosis and repair side of things, that is one tough problem to solve. After all, if it is not broken, what do you fix? Because the problem is intermittent, it does help in narrowing the possible causes.
For example the ignition system. If the spark plugs, plug wires or ignition coil packs were the cause, the problem would be more constant. Why? Once an ignition related component starts degrading the condition becomes more pronounced. Apply the same thought process to the fuel system. If the fuel pump was starting to fail causing a drop in fuel pressure it would be very unlikely that the pump would get better for 2 to 3 weeks and then act up again. If the engine had a mechanical problem, it would be just as unlikely to get better for weeks at a time and then go bad. It would be a unique situation for any one of these systems to act up like that. This leaves computers and emission controls. Either one of these systems can do what you're describing. It is unlikely the computer is bad, but it is possible that there is a poor connection.
A faulty power supply or ground connection can cause the computer to do some bizarre things. Lastly and what I believe to be most likely is the emission controls. I would target the EGR system. The EGR valve can stick open causing the engine to run rough resulting in a random misfire code to be set. Because the computer's program prioritizes, a misfire code would go to the top of the list and the computer would not be running any test on the EGR system at that time. If the EGR valve, EGR solenoid or the Pressure Transducer for the EGR valve were to stick, they could easily return to normal once the engine was turned off. Restart the engine and the problem would be gone and each component would test just fine. In the event, you determine the EGR valve is the problem 'do not' buy an aftermarket EGR valve. Get a factory EGR valve; it comes with a new solenoid and pressure transducer as well.
Chrysler Concorde - Miss in the 5th cylinder
Chrysler Concorde
My 98 Chrysler Concorde was running great with only 70,000 miles. Then the check engine light came on. The reading showed a miss in the 5th cylinder. My mechanic has replaced and checked everything, including the computer module that "talks" to the 5th cylinder, but the miss is still there. He says that replacing the intake gasket is the only thing left to try. Have you heard of this problem before Doc?
My 98 Chrysler Concorde was running great with only 70,000 miles. Then the check engine light came on. The reading showed a miss in the 5th cylinder. My mechanic has replaced and checked everything, including the computer module that "talks" to the 5th cylinder, but the miss is still there. He says that replacing the intake gasket is the only thing left to try. Have you heard of this problem before Doc?
Chrysler - Check Engine light
Chrysler
I have a '96 Chrysler with 2.2 engine with 130k miles. The Check Engine light just came on. The code is for the EGR valve. I suspect it is just carbon. However, I was wondering what short/long term problems might I run into if I do not replace the part? It is quite expensive.
I would suggest not jumping to the conclusion that just because you have an EGR related code that the valve is the fault. Carbon deposits can be removed/cleaned from the EGR valve if that's the problem. There are problems with the EGR system passages becoming restricted but a new valve won't fix that, they need to be cleaned. There are also vacuum hoses that are known for breaking, along with a lift sensor, control solenoid and a vacuum control valve as well. An inoperative EGR valve does increase the amount of exhaust pollutants that are emitted. Unbelievably, an inoperative EGR system on your vehicle will also reduce gas mileage. A little time invested checking and inspecting the EGR system could provide a new return.
Chrysler - Engine oil, sludging up
Chrysler
My 1996 Chrysler with a V6 engine has what appears to be a problem with the engine oil.........It is sludging up, when I pull the dipstick it is covered by a browny coloured sludge. My neighbour says I don't change my oil on schedule. However, I do change it every 3,000 miles. What's happening Doc?
A couple of things can be causing this Harley, all engines have to breath and if the components that help it do this are not working or themselves plugged up, then you see the consequences on the dipstick. A clogged crankcase ventilation system can cause deposit build-up, which will block oil pump screens and oil passageways, hindering lubrication to the entire engine. The cause is mainly cold engine start-ups which cause the engine to spew out lots of unburned fuel, acids, crud and condensation causing oil and water emulsion. One needs to drive so that the engine reaches normal operating temperature enabling this stuff to burn off. If you make many short trips and the engine doesn't reach normal operating temperatures then this is what causes the emulsion, oil changes need to be made more frequently say every 1,500 miles rather than 3,000 miles. Check the PCV ( positive crankcase ventilation valve ) replace if plugged up, also check the hose that leads to it, this may be plugging up to, if your vehicle is also fitted with a crankcase filter, usually inside the air filter, change that too. The other way you would get water in the oil is through a head gasket, head(s), or engine block crack. This you would have to get checked out at a garage with a ' dye ' test on the coolant, or you can purchase some automotive litmus paper and check the coolant yourself, the litmus paper will change color if there is one of these three problems evident. I hope it turns out to be just the crankcase system that needs attention only, it's the cheapest fix!
Chrysler Concorde - Oil pressure sending unit
Chrysler Concorde
Dear Doctor, My son owns a 1993 Chrysler Concorde. The oil pressure-sending unit, because it was leaking was replaced. Now it is doing the same thing after 2 months. Could there be too much oil pressure causing these to leak?
Too much oil pressure in a ’93 Concorde? Not likely Carl. The oil filter would have bubbled like a balloon or just blown off the engine. Oil pressure switches like many other automotive parts come in different levels of quality. The really affordable stuff is just a problem waiting to be bolted in. Also oil pressure switches can be damaged when being installed. Hey, that happens to the best of us. Last but not the least, the product is defective. We’ve practiced more than once at replacing new parts that just weren’t made right. It sounds as if a replacement oil pressure switch is your next job………Make sure this time it’s an OEM part from the Chrysler parts department. Thanks for the question.
Chrysler Voyager van - Transmission/gearbox problems
Chrysler Voyager van
We took our Chrysler Voyager van to a lube shop and had an oil & transmission fluid change. Afterwards it started showing a problem when we came to a stop; it momentarily shifts to neutral and then to low. In the morning when it is cold it pauses longer than normal when putting it into gear before the transmission engages. All other driving & shifting is normal. We took it to the dealer and they say it now needs a new transmission. We don't know if they're being honest or what. Have you ever heard of this problem?
There are two possibilities. One is that your transmission is in fact in need of service. It was just the unfortunate coincidence that it had been recently serviced. But, before spending the money to have your transmission rebuilt, I would get a second opinion. In addition, you may want to have the transmission filter inspected. The transmission in your Voyager is likely a model 41TE. The filter that fits this transmission closely resembles the filter for another Chrysler vehicle that has a model 42LE transmission. Here's the problem, these filters may look alike but they are different and cannot be swapped. Chrysler Motor Corporation warns that the 42LE transmission oil filter is not interchangeable with the 41TE transmission oil filter. An incorrect application of the transmission oil filter may cause transmission damage. Get to it ASAP.
Chrysler Sebring - Running Problems - Problem keeping the car running
Chrysler Sebring - Running Problems
I have a '99 Chrysler Sebring, I've put in a new battery and a new alternator and I'm STILL having a problem keeping the car running. I took it on a three mile trip and I had to charge it 6 times (I'm not joking ). Before I go to a shop (I'm a female and tend to be taken advantage of because I'm absolutely stupid when it comes to cars) can you give me an idea of what else could be wrong. I'm very aware of your knowledge, so I feel I need more information from you as to what's going wrong. Thanking you in advance!
Give yourself more credit Danielle, your asking a smart question! A vehicle's charging system can be simplified into two categories: a storage and operating system. The battery is a storage device for electrical energy. The electricity stored in the battery is used primarily for starting the engine. Once the engine is running, the alternator takes over providing the electrical energy to operate the engine and all accessories, at the same time replenishing the electrical energy in the battery that was used to start the engine. If you have to repeatedly charge the battery to keep your car running, then the charging system is probably not operating correctly. Ask the garage to do an AVR test ( Amps, Volts, and Resistance ) a qualified technician should have no problem in diagnosing the cause for your charging system problems
Corsica 2.8 mfi - Transmission locks in top gear
Corsica 2.8 mfi
I have just bought a 1988 Corsica 2.8 mfi, after the car has been driven for a few miles the transmission locks in top gear. Can you adsvise me what to look for?
Hi Kalie! You probably don't have any records of what regular maintenance was done throughout the life of this car before you took possession? If you are able to get information on the previous owner I would ask them if they kept records and would it be possible to have them as your starting your own folder. After all if he/she has them they wouldn't be of use to him/her now.
As for the problem you have, it sounds very much like you need a 'Torque Converter Clutch Solenoid '. This usually gets plugged with silt and fine pieces of metal and the oil cannot flow freely causing the transmission lock-up to stay engaged. It's almost like you have a standard transmission and your moving away in top gear. When you slow down with this problem on auto's it doesn't downshift but stays in high gear and this is what you are feeling. When this solenoid is changed the transmission shop should do a ' service ' on the trans at the same time, ie; new fluid, filter, gasket and pan cleaned, also the trans oil pan magnet cleaned or replaced.
Dodge Grand Caravan - Fuel gauge problem
Dodge Grand Caravan
When I get to just above half a tank on the petrol gauge the low fuel light comes on and then the gauge drops to empty on my ‘91 Dodge Grand Caravan. Would this be the gauge or the unit inside the tank itself?
I would without a doubt say that the sending unit in the gas tank that reports the fuel level is for sure failing. Because of the vehicle’s age I would suggest replacing the fuel pump when you have the sensor/sending unit removed from the gas tank for replacement. Why? The fuel pump is part of the gas gauge sending unit assembly so the labor cost should be no different.
Dodge Dakota - Ping from pre-ignition
Dodge Dakota
I have a '97 Dodge Dakota with a 3.9 L engine. Ever since I bought it new, it has had the ping from pre-ignition. When I run mid grade petrol it diminishes but it's always there. I've had the programme (computer) flashed, cleaned the injectors, retorqued the manifold bolts, replaced the PCV and breather, cleaned the throttle plate. On the analyzer it doesn't show any faults... Could the TPS need replacing?
No, I could not say that replacing the Throttle Position Sensor (TPS) on your vehicle would correct a spark knock. But are you aware that with a factory scan tool for Chrysler vehicles, you can go into the program and initiate a program to change the spark timing? This is not to be confused with flashing the computer in other words (reprogramming with new software)
In the operating software for Dodge , Plymouth and Chrysler vehicles there is a way to alter the spark advance/retard schedule of the ignition system. This module of the software allows for a finer level of engine tuning. I would suggest investigating this procedure to possibly correct your spark knock problem.
Dodge Ram 150 Day van - Van back firing
Dodge Ram 150 Day van
We have a 1986 Dodge Ram 150 Day van with approximately 68,000 miles on it. For quite some time we have had a problem with the van back firing and stalling at any stop we make. Our mechanic has worked on it and can’t seem to find the problem. The carburettor has been rebuilt twice. The choke adjusted, replacement exhaust tube & emissions valve, new spark plugs & wires, PCV valve and petrol filter.
The back firing is the main problem and occurs whenever you accelerate rapidly and then let off the acceleratorl. One of the last times it back fired, it blew the silencer apart.
This is very frustrating and expensive. Any help you can give us would be greatly appreciated.
From your description it is likely that there is a problem with the air injection system. The air injection system provides additional oxygen to the exhaust to assist in burning remaining gas and reduce pollutants. But there is a time when there can be no air injection occurring, that is during deceleration.
When you let off the gas pedal of your vehicle to slow down quickly, for a brief moment there is not enough oxygen available to burn the gas in the engine. This unburned fuel is dumped into the exhaust. Here’s where it can get exciting! If by chance, additional oxygen is introduced in the exhaust with the unburned fuel, kapow! The unburned fuel will ignite, alerting all innocent bystanders of your presence. The intensity of the explosion will vary from a mild bubbling in the exhaust to an impressive display that will illuminate the whole underside of your vehicle as it blows the muffler apart.
The component responsible for preventing this untimely explosion is called a diverter valve, makes sense doesn’t it? The diverter valve uses a vacuum signal from the engine to determine when a sudden deceleration is occurring. At which point it will prevent the air injection system from pumping oxygen into the exhaust. Then it will allow the air injection system to return to normal operation.
Have your technician inspect the diverter valve, vacuum hoses to it and any controls such as electric switches that are responsible in controlling the system. I’m sure he/she will find the cause.
Dodge 2500 Ram - Wheel Wobble
Dodge 2500 Ram
I have a ‘96 Dodge 2500 Ram 4x4 Diesel. When I put it in 4 wheel drive & turn either way more than about half way, the wheels pull irregularly like the wheels are wobbling during a slow turn. Is that normal?
Nelson..... I would suggest having your front axle joints checked. The front four wheel drive axles on your vehicle use a u-joint at each front wheel. Your Dodge is of the right age where the u-joint could be dried out and binding internally. A binding u-joint will cause a wobble or jerky motion of the vehicle when the steering is turned. The sharper the turn the more pronounced the problem. Do not wait in having your vehicle’s front axle/u-joints inspected. If a u-joint fails it can damage the axle, which will drive the cost of repair up substantially Nelson.
Dodge Dynasty - Brakes Hose & Overheating
Dodge Dynasty
We have a '90 Dodge Dynasty with a 3.3 engine. The front passenger tyre gets so hot that we have to pull over and let it cool down. We had it in three times to a garage and replaced the caliper twice. The last time we replaced the caliper we replaced the rotor, pads and found the caliper still does not work properly so we brought it into a brake shop hoping that they could find the problem. He said there was an air bubble on the opposite side, that was probably putting pressure on the one that was giving us the problem so we kept our fingers crossed and drove it for about a day without a hitch. Then, low and behold we were out driving for about five minutes and the tyre started to smoke really bad and you could smell something burning. We pulled over for about 20 minutes and then we managed to get it home. This is so annoying that none of the mechanics or the brake specialists can tell us what it is...
Hi Jessie and Mike, I'm kind of surprised that not one mention was made of the brake hose. Your vehicle is plenty old enough to have problems such as degrading brake hoses. The inside of the brake hose can be swollen and even coming apart. Under the right conditions the brake hose can actually prevent the release of brake fluid. An air bubble in that or any other brake line won't do that. So much for calling oneself a ' Brake Shop ' I would have thought their ' expertise ' would have told them to at least suspect a brake hose.........
If you can get the brake to stick, pull into a garage and ask them to jack up that wheel. Once the wheel is up, try to turn the wheel to be sure it's still binding/sticking. Then with a wrench, open the bleeder screw to that brake caliper. If suddenly the wheel turns free you know brake fluid pressure was holding the brake on not the brake caliper. If the wheel turns free the brake hose is definitely suspect.
Dodge Caravan - Cooling fan failings
Dodge Caravan
Hello Doctor John, the cooling fans on my ‘98 Dodge Caravan won't shut off. I have to pull the fuse to stop them. Where is the switch that activates them?
Hi Gerry! I don’t think you’ll find that there is a switch problem. More often, it is a controller/module for the cooling fans that has failed. If you look closely on the inside of the driver’s side of the frame/unibody right next to the radiator you’ll see a small black box setting on an aluminum plate that is held by two screws. It’s likely that one of the screws is broken/missing.
That aluminum plate is a heat sink for the fan module. When the screw that holds the module to the frame breaks there is not enough contact of metal to transfer the heat and the module fails. The result is both fans are on all the time or not working at all. Dodge has an updated module and screw kit to correct the problem. Check with the dealership you bought the vehicle from originally.
Dodge Caravan - Wheel balancing problems
Dodge Caravan
I've been told by several mechanics that all four wheels of my 1988 Dodge Caravan are bent. The car has never seen harsh driving conditions; pot holes, etc. The car has been through numerous sets of tyres since I bought it new. The front end seems to have a shimmy no one can fix. After balancing the tyres everything is fine for a short while but then the shimmy returns. Can this be caused by bent wheels? And how would all four wheels become bent without having been in an accident or something like that?
Gee, seven techs say your rims are bent, maybe one of them is right. Tire rims do not have to be in an accident, or hit a pot hole to become bent. Rims can be bent from the factory, or by bumping the tire into a curb. Damage can also be caused by incorrect mounting of a tire on a rim, or even as the lug nuts are being tightened.
Bent rims can be seen when a new tire is being balanced, the tread of the tire will wobble. Balancing will only cover the bent rim problem for a short time. Because the tire does not run true to the road, due to the bent rim, it will wear incorrectly and never provide a smooth ride. New rims are what's needed.
Dodge Ram 150 Day van - Back firing
Dodge Ram 150 Day van
We have a 1986 Dodge Ram 150 Day van with approximately 68,000 miles on it. For quite some time we have had a problem with the van back firing and stalling at traffic lights and corners. Our mechanic has worked on it and can't seem to find the problem. The carburettor has been rebuilt twice. The choke adjusted, replacement exhaust tube & emissions valve, new spark plugs & wires, PCV valve and petrol filter.
The back firing is the main problem and occurs whenever you accelerate rapidly and then let off the petrol. One of the last times it back fired, it blew the silencer apart.
This is very frustrating and expensive. Any help you can give us would be greatly appreciated.
From your description it is likely that there is a problem with the air injection system. The air injection system provides additional oxygen to the exhaust to assist in burning remaining gas and reduce pollutants. But there is a time when there can be no air injection occurring, that is during deceleration.When you let off the gas pedal of your vehicle to slow down quickly, for a brief moment there is not enough oxygen available to burn the gas in the engine. This unburned fuel is dumped into the exhaust. Here's where it can get exciting! If by chance, additional oxygen is introduced in the exhaust with the unburned fuel, kapow! The unburned fuel will ignite, alerting all innocent bystanders of your presence. The intensity of the explosion will vary from a mild bubbling in the exhaust to an impressive display that will illuminate the whole underside of your vehicle as it blows the muffler apart.
The component responsible for preventing this untimely explosion is called a diverter valve, makes sense doesn't it? The diverter valve uses a vacuum signal from the engine to determine when a sudden deceleration is occurring. At which point it will prevent the air injection system from pumping oxygen into the exhaust. Then it will allow the air injection system to return to normal operation.
Have your technician inspect the diverter valve, vacuum hoses to it and any controls such as electric switches that are responsible in controlling the system. I'm sure he/she will find the cause.
Dodge Neon - Brake noise & Water Leaks
Dodge Neon
I own a 2000 Dodge Neon. I have two problems that I was wondering if you ever heard of: 1. The brakes squeal very loud when I come to a stop, after the car has sat for about 3 hours or so. 2. Water leaks to the rear passenger floor. I have taken it to the dealer multiple times and was told nothing could be done. Any advice would be appreciated.
I just love that answer, "Nothing can be done!". If a dealer is telling you that nothing can be done, they're telling you they don't care.
With an answer like that the first thing I'd do is have no business with that shop anymore. Brake noise can be torture at times to get rid of but there is a solution. I have had many e-mails on this very problem, many dealers were telling thier customers, " It's called Neon Squeal, you have to live with it! " Isn't that nice........
Well I have found if you fit the new ceramic pads you'll not only get rid of the noise but the black dust that accumulates on the wheel rims. These pads also disipate the heat faster, last longer as well. They are a little more expensive, but what's price when you can live without the squeals.
Now the water leaking into the passenger compartment is just not acceptable! Water leaking into the vehicle will cause to vehicle to rot/rust from the inside out. Not to mention the mold spores that will grow.
With that in mind and many visits to the dealer that says nothing can be done, you must have lemon! If you have a lemon then it is time to check on your lemon laws, I assume you have those in the UK? You didn't buy a swimming pool you bought a car, so they should buy it back.
Dodge Dakota Sport - Loud tapping on start up
Dodge Dakota Sport
I have a '99 Dodge Dakota Sport with 29,000 miles on the motor. When I first start the motor it starts tapping real loud for about 3-5 minutes then calms down. I called the dealer service and they say it's normal for a 3.9L engine. I change oil at every 2000 miles and use Havoline 10w 30. Can you offer any good advice on this matter? It would be great
Where do they get these service people from that don't appear to have any real training? I cannot believe that this particular service individual would have the testicular courage to try laying that kind of a line on a customer. It's sad because the customer is not sure what to believe.
Yes Steve, your Dakota has a problem. Find a different repair facility to address your vehicle's problem. Because the advice you're receiving is just as much a problem as your vehicle's!
Dodge Neon - Brakes
Dodge Neon
Hi Doctor John , I need help. Could you tell me where to find a picture of the left rear wheel and all the parts for my 2000 Dodge Neon? I have to remove my tyre and fix what may be the brakes or a spring.
You don't need a picture Cheryl, your vehicle comes equipped with a mirror image. Just remove the wheel and brake drum on the rear right side of the car, and use that as your picture. If it turns out that you do need brakes on the left side, I would certainly do both rear wheels at the same time. A box of brake shoes have two pair in them anyway.
Dodge 4WD - Heater blows only luke warm air
Dodge 4WD
Doc, When thermostat opens on my '96 Dodge 4WD the heater blows only luke warm air. I took it to the dealer; they put in a new water pump and thermostat. I still have the same problem. Do you have any ideas?
Hi Paddy, If the coolant is at the correct level and the thermostat is operating at the correct temperature then I'd suggest moving your inspection toward the heater. Heater cores can become blocked or restricted. With the engine fully warmed up and the heater blower motor off, compare the temperature of the upper radiator hose with the hose to and from the heater core.
The temperature, in general, should be about the same on all three hoses. If you find that one of the heater hoses is cooler, it is possible that the heater core is restricted. To confirm, have a technician check the flow rate through the heater core. If restricted I would suggest a replacement with a full cooling system flush.
Now depending on which model Dodge you have, be aware there is a problem with the cable from the heater control that operates the blend door for the heater. The problem is that the cable slips on the arm of the blend door. When this happens the temperature from the heater can't be controlled correctly. The fix is easy, requiring only an adjustment on the blend doors arm to prevent the problem.
Dodge Ram - 4 wheel drive = Nasty noise!
Dodge Ram
Doctor John, When putting my '99 Dodge Ram in 4-wheel drive something makes a nasty noise. It used to only happen when it was cold out, now it's all the time. Is this the transmission or something to do with the front axle?
Misty, If the grinding noise seems to be coming from the front of the vehicle when you engage the 4-wheel drive then I would suggest checking the axle shift motor that is located on the passenger side of the front differential. The axle shift motor is vacuum operated. When you select 4-wheel drive a control switch on the transfer case directs a vacuum signal to the axle shift motor. The right side axle is a 2 part component. The vacuum causes the axle shift motor to slide a collar (with gear type teeth) that engages and locks the 2 parts together for 4-wheel drive. If the vacuum supply is weak, the control switch on the transfer case is failing, or the axle shift motor is not working correctly the collar that locks the 2 parts together will not fully engage. This partial engagement causes the gear/teeth of the sliding collar to grind against the shaft it is trying to engage. Don't let this problem go! Grinding parts together for too long will mean you'll need more dollars for more parts. Get it into the garage ASAP.
Dodge Dakota - Engine tapping when first start up
Dodge Dakota
I have a 99 Dodge Dakota Sport with 29 miles on the motor. When I first start the engine it starts tapping real loud for about 3-5 minutes then calms down. I called the dealer service and they say it's normal for a 3.9L engine. I change oil at every 2000 miles and use Havoline 10w30. Can you offer any good advice on this matter? It would be great.
It's funny and very sad at the same time Stephen. Why? because I cannot believe that a service person would have the gall to try laying that kind of line on a customer. It's sad because the customer is not sure what to believe now. Your Dakota has a problem. Find a different repair facility to address your vehicle's problem. Because the advice you're receiving is just as much a problem as your vehicle's! I you want to e-mail me again I can send you any TSB's ( technical service bulletins and recalls on the vehicle.
Dodge Ram 3500 - Transmission slip after bump
Dodge Ram 3500
I have a '01 Dodge Ram 3500 24 overhead valve 4X4. A lorry backed into me and my transmission started slipping. The insurance company is saying I'm trying to capitalise on the situation. It was parked with the front wheels against the curb. What is your opinion; would this cause damage and make the transmission to slip and go out of gear when I had never had any problems before?
Jim, I find it hard to believe that having another vehicle back into yours would cause damage to the transmission. Particularly with the engine off and the transmission in park. If things were just right it may damage the parking pawl of the transmission, but the parking pawl is pure mechanical. You could snap it right off and it would have no affect on forward or reverse gears, it's just when you put the transmission in park the truck would roll. May I suggest that you ask the insurance company to leave that end of the claim open. When you have the transmission problem fixed have the technician performing the repairs document his/her inspection and diagnosis of the transmission. If damage from the type of impact you describe is found, that could cause your complaint, with the documentation from the transmission technician, the insurance will likely write you a check.
Dodge Grand Caravan - blowing blue smoke
Dodge Grand Caravan
I own a 1999 Dodge Grand Caravan 125,586 miles. It is blowing blue smoke out of the exhaust pipe. I put new spark plugs in it then I ran it for a minute and checked one spark plug for oil on it. There was oil on it. Please tell me what is going on with it.
Blue smoke is from oil burning. Your engine has internal problems such as piston blow by, valve stem seal problems, broken/worn piston rings, etc. It may be time for an engine overhaul Chuck. Get the garage to do a compression test on it first.
Dodge Dakota truck - Sludge Build up
Dodge Dakota truck
I have a '94 Dodge Dakota truck 6 cylinder, 4 wheel drive. I change the oil every 3,000 miles but I have trouble with SLUDGE in the oil pan. This problem caused me drop the sump and clean it out twice already. What can I do to keep this sludge from building-up?
Any chance that you're a short trip driver Derrick? Short driving trips are really rough on the engine oil. It's known as harsh driving and because the engine rarely reaches normal operating temperature it doesn't burn off all the crud, acidity and condensation that a cold engine produces when it starts up. I would suggest good quality oil and base your oil change intervals on time and not mileage if you're having a sludge problem. If you want to start with mileage then start with changing it every 2,500 miles and if you have to, go down in increments of 500 miles. I would also check the breathing ability of the engines PCV ( positive crankcase ventilation) system, that could be plugging up with crud to.
Durango - shifting points seem a little off
Durango
I recently had my transmission removed and rebuilt in my 1999 Durango, and since I got it back, the shifting points seem a little off, but the main problem I'm having is that if it sits over night, and I first start it and put it in gear to either back or pull out of my driveway, the Durango won't move, I give it throttle and it seems like there is no gear whatsoever, but after a couple seconds, 10 or more it goes in gear and works fine. The longer the Durango sits, the longer it has no drive gear, but before it engages, you hear the pump and everything but it still won't move, then it goes in and is fine untill it sits again. A tranny shop told me that they're 100% sure it's the check valve in the tranny line and they said they have to replace that. When in fact I changed that the day I got the Durango out of the shop. And if it sits for a couple days there's a puddle under it from tranny fluid, but I believe that's just the pan gasket. And the transmission shop has it now and says its fine, its normal and has no problem going in to gear for them. Any idea what the problem could be.
Your problem Jason is the result of an internal leak in the transmission. The torque converter drains back into the transmission overnight. We call this "morning sickness." When the truck is started, it can not move until the transmission refills the torque converter. When the truck sits for several days, the torque converter over-fills the transmission to the point that the fluid leaks out of the vents.
Dodge Durango - leak in the heater core
Dodge Durango
2001 Dodge Durango mileage: 195,000 miles. I have a leak in the heater core. It leaks into the passenger compartment. What needs to be removed to get to it and repair or replace it, I am a DYI kind of feller?
Replacing the heater core on your truck is an easy job Eric. The heater core cover under dash must be removed. Next, remove the heater housing to replace heater core.
Dodge Ram - Petrol cap fallen into tank!
Dodge Ram
I was adding petrol into my 2001 Dodge Ram from a petrol can and the stopper fell into the petrol tank. What can I do, and what trouble am I going to have until I get it out?
Don't you just feel special Sharlene when stuff like that happens? I wont ask you what you mumbled under your breath when that happened. Myself, if I could still add gas without any problems I'd leave it in the gas tank. But you know what, still hold on to your gas can. Why? In the area of 100 to120,000 miles your Dodge will most likely need a fuel pump. The fuel pump (actually called a fuel pump module) is mounted in the gas tank. So when the fuel pump module is replaced, ask the technician to save that piece of plastic that is floating around in the tank. Then your gas can will be complete once again.
Ford Escort - Overheats if idling too
Ford Escort
Doc John, my '93 Ford Escort overheats if idling too long. The cooling fan will not come on and it is not a fan motor or a relay problem. Two mechanics say its electrical. The earth was lost somewhere. One says it will take hours to locate the problem, and labour alone will cost a few hundred pounds. The other laughed at this and said he can find it and fix it in minutes by putting in a new earth strap. Who's right? Also the clock does not work, but comes on occasionally for a few minutes. Any connection?
The clock wiring is not related to the cooling fan. The ground for the cooling fan motor can be located on the left front of the vehicle near the left headlight. I would suggest checking there first. If the connection is good, go with technician B's answer and run a new ground wire.
Mercury Topaz - Grinding/clacking on Steering
Mercury Topaz
My Mercury Topaz has developed a horrid grinding/clacking noise when turning the steering wheel to the right. Any ideas on what could be causing it?
My first impression Leanne? Your vehicle has a failing outer CV-joint. I would not recommend driving the vehicle without having the problem inspected. Operating a vehicle when there is such a pronounced noise is really asking for trouble. You're vehicle could leave you stranded on the side of the road or worse, result in injury! Waiting to address the problem is only going to drive the cost up! Get it checked out as soon as possible.
Probe GT V6-24V - Weird smoke problem
Probe GT V6-24V
I have a 1999 Probe GT V6-24V with 188,000 miles. Here's a weird one for you Doc, I've been noticing this for a long time and even asked local garages with no success. When I stop at a junction (downhill) everything is fine but when I start accelerating away the car smokes out the back...yet if I am at a level junction or inter-section and accelerate...it is fine.... I also noticed this when I take certain turns too fast and accelerate...SMOKE.... I have no idea what this is.... HELP!
I have found similar problems with other cars approximately 140,000 or more miles. Replacing the valve stem seals reduces the oil use and smoke. They are made out of rubber and over time become hard and brittle and no longer seal. If that doesn't help you may have a broken piston ring. A wet and dry compression test will help with diagnosing either problem after seeing both resulkts of the wet and dry test figures.
Mustang - power Brake Booster
Mustang
Should I be able to pull a vacuum on my power booster when it is removed from my 1968 Mustang or on my
work bench? I have two rebuilt units, but I cannot pull a vacuum on either one...on or off the car...
any advice?
Yes, you should be able to operate the booster off the car, or on it, by attaching a vacuum source to the vacuum connection. However, it takes quite a bit of volume and a good strong pull to get a good vacuum, so depending on what you are using to produce the vacuum it might not be enough to get the booster to work. If you have a vacuum gauge, tee it into the line to see if you are getting at least 15 In. Hg. of vacuum - more is better - your car's intake manifold will pull about 20 In of vacuum if it is in good shape, at idle.If you cannot develop vacuum by using the car's intake manifold, and the engine is healthy, something isn't right - if you cannot find a leak, and nothing is pushing on the brake pedal linkage, I'd say your boosters are bad. That is very unlikely, however, because any reputable booster rebuilder would have bench tested it. If you are trying to do this with a vacuum cleaner, it probably isn't generating enough of a vacuum to operate the booster. Try doing the same thing by connecting to the intake manifold and starting the engine.If you are using an AC service type vacuum pump, it will not generate enough volume to do this unless you tee in a large vacuum reservoir in the line - a reserve tank, in other words, and let the pump run a long time to build up 20 inches or so of vacuum before you try the booster.
US Ford Probe - Transmission jumps
US Ford Probe
Doctor John, When I'm driving down the road in my car and I put it into fifth gear, the transmission jumps out of fifth gear into neutral. I put it into fourth and then try into fifth gear again but it does it once more. It is a '99 US Ford Probe , what is going wrong with my car and how can I fix it so it is more dependable?
From your description Brad, I would say that the transmission is going to have to come out of your vehicle to be rebuilt or replaced. You may ask if it is a shifting linkage issue, maybe an adjustment? If it was an adjustment issue you would have a problem with first & third as well. The problem is not going to get any better and you will likely start hearing other noises from your transmission. If you want dependability, then a replacement or a rebuild will be the answer to that problem.
Mustang 4.0 Litre - Ticking V6 engine
Mustang 4.0 Litre
Concern about a problem with ticking V6 engine Mustang 4.0 Litre.
This ticking noise in these 4.0L SOHC engines is most likely coming from the timing cassettes. Namely the left one. I've experienced this problem in a Ford Ranger coming into the shop that had been serviced poorly. The engine ended up seizing and being replaced, but I have also experienced it in Explorers so Mustangs can easily be added to the list. The cassette will wear out or break. To repair this the front cover, intake and valve covers must come off. The engine can stay in the vehicle unless the RIGHT timing cassette also has to be replaced.
I think the reason this seems to happen after an oil change is because after the new oil filter is installed the engine runs "dry" for a short period of time. If you have ever witnessed this for yourself it makes an awful noise. Then, as soon as the oil pump fills the oil filter the oil can be distributed to the rest of the engine. This would not cause a problem on most engines. But the 4.0L SOHC engine uses hydraulic tensioners to keep the cassette chains tight. When the engine runs "dry" the chains are allowed to become slack, then when the oil pressure hits the tensioner it pulls excessively on the chain and cassette causing chain stretch and possible severe damage. The cure for this is to fill the oil filter with new clean oil prior to installation. I hope this will help some of you out there with 4.0 liter SOHC engines to make sure the lube guys at the garages know and understand this. You must insist that they fill up the oil filter prior to installation. In fact if you print this letter off you can give it to them to make sure they understand why you are insisting.
Ford Crown Victoria - Where is the reset on the computer
Ford Crown Victoria
A small hose came off that's under the petrol tank in a black plastic box on my 98 Ford Crown Victoria. I plugged it. This has to do with emissions I think because it caused the engine light to come on in the dashboard. Where is the reset on the computer?
When you say you plugged the hose Fred, I wonder, did you plug it back into something or did you just plug the end of the hose? The black box you're likely referring to is called an evaporative canister. This canister has a vacuum/vapor hose, but it also has a vent hose. If the vacuum or vapor hose falls off it will cause the check engine light to turn on. The vent is what it is; a vent to allow for needed air movement. Plugging the vent hose could create problems. As for the other hoses, just reconnecting them to the correct fitting should be the fix. Each day you drive your vehicle the computer runs a test on the emission controls. If you correctly repaired the problem, the computer would confirm the repair and turn the check engine light off in a day or 2 of driving. If it doesn't turn off, the repair was not effective or there is another system problem. If you need to rush the check engine light, just disconnect the battery. This will clear the computer and every other darn computer memory, radio etc., and turn the light off. But, if a problem remains the check engine light will soon return and will need to be diagnosed by the tech performing a " fault code review ".
Ford F150 - No Heat
Ford F150
I have gone through all of the vacuum lines and misc. vacuum motors and checked for leaks or defects for the heater on my '90 Ford F-150. I have replaced the heater core and the thermostat. I still cannot get heat into the cab. What can I do next? Could it be a water flow problem (not enough water being pumped through the heater core)?
A water/coolant flow problem Jamie could easily explain your no heat condition. When the engine is at operating temperature both the supply and return heater hose should be hot. As for coolant flow, it should be in the area of a garden hose. In most cases a garden hose will not flow as much as the flow through a heater with the engine revved up. If flow is low a water pump may be needed to correct your heat problem.
Ford Taurus - Popping in the rear
Ford Taurus
We have been hearing a popping in the rear end of our '93 Ford Taurus. It seems to do it more when turning to the right.
There are a couple of common problems John that occur with vehicle age on Ford's Taurus or Mercury Sable for that matter. The more common of these noises is the rear sway bar links. The bushings on the links will wear and then that causes movement of the bar or, the bolts will rust and break. This allows the bar to slap the remaining parts of the sway bar link which could be described as a thump or popping noise. Get your local garage to put it on the hoist and have them check it out. The cost of repair isn't an expensive one.
Ford Taurus - Adding McPherson struts
Ford Taurus
I have a ‘93 Ford Taurus SHO. In order to put new front McPherson struts on do my calipers need to be taken off? Also, does it have anything to do with my brakes??
Sarah, On most vehicles the brake hose to the brake caliper is supported by a bracket that bolts to the strut/shock assembly. Often, but not always, to remove the strut requires moving the suspension in a manner that will put a damaging strain on the brake hose unless the brake caliper is removed from the assembly. It’s not really a big deal, it’s just part of how the job is done. Normally one uses a wire coat hanger to create a hook each end to help suspend the caliper and take the strain off that brake flex hose.
Ford Taurus - Windscreen wipers problems
Ford Taurus
I've got a problem with my 1991 Ford Taurus that I need a bit of help with. I was having two problems with my windscreen wipers: First, the intermittent wiper settings would not work right; they would work on low and high intermittent but nothing in between. The second is most of the time, but not always, the wipers forget where their "home" or "down" position is. When you turn off the switch, the wipers go all the way up instead of down.
This past weekend I replaced the wiper/turn signal/dimmer switch. It cured the intermittent problem just fine but the wipers still don't know that they should be down when the switch is turned off. They go all the way up.
HELP Doc! I don't want to have to take the car to someone. Any ideas?
Shaun, A failing wiper switch can cause the loss of intermittent wiper operation. Now that you have the first problem out of the way let's talk about the windshield wipers not finding home or getting lost.
In the trade we call the resting point of the windshield wipers the park position. The park position is determined by switching (controls) inside the wiper motor assembly. Because the windshield wipers park themselves erratically it is reasonable to think that the switching inside of the wiper motor is failing.
Due to the age of the vehicle, I recommendation replacing the wiper motor. Now when replacing the wiper motor I show a Technical Service Bulletin (TSB) # 95-8-2 for an updated wiper motor wiring harness. This update effects many Ford vehicles from the late 80's up, so call your Ford dealership and see if this wiring harness is still available. Most dealers carry parts for cars up to ten years, so it may have to be a special order part.
Ford Explorer XLT sports truck - Fuel Reset Switch
Ford Explorer XLT sports truck
Dr. John I have a 1992 Ford Explorer XLT sports truck where might I find the
fuel reset switch? It is not anywhere to be found.
Jacky, You will find this under the carpet on the passenger side close to the topof the carpet against the firewall, pull the lip of the carpet down you'llsee it slightly to the left of the passenger kick panel.
Ford F150 4x4 extended cab - Transmission makes a clunk sound
Ford F150 4x4 extended cab
I have a '96 Ford F150 4x4 extended cab. When stopping at lights the driveline or transmission makes a clunk sound. Is there a recall or a fix for that?
First, be sure that your universal joints in the driveshaft are in good condition. If they are, there is a bushing at the end of the transmission (transfer case on four-wheel-drive vehicles) that supports the front of the driveshaft. It is not uncommon for this bushing to wear and when this bushing becomes worn, a driveline clunk and/or vibration can occur. The bushing is not costly and is easily serviced.
Ford Taurus - Transmission problems
Ford Taurus
I recently talked to my Dad, who has a '95 Ford Taurus with some transmission problems. I am not sure what the actual problem is, but I am a little disturbed by something the mechanic said to him. He said there were metal flakes in the pan, which could effect the power steering system. He said both systems were one in the same, (they have been combined). If this is the case, why does the vehicle have its own power steering reservoir as well as the transmission servicing tube which the dipstick slides down into? What I am worried about is the integrity of the mechanic who happens to work in one of the major transmission repair garages and the possible shafting he is giving to my father.
William, the power steering and automatic transmission are two completely different systems. They do not share fluids in any way! In fact they use different fluids!
Unless your father misunderstood what the tech was saying, you have great reason to be concerned! I suggest calling your father and confirm what he is telling you. If the story stays the same steer him away from that shop. Why? Because it sounds like he's going to get a power steering rack and transmission along with that shaft!
Ford Explorer - Noises
Ford Explorer
Doctor John My '99 Ford Explorer Sport has a howling noise (at about 40 to 45 mph).
I have approximately 33,000 miles on the vehicle. The Dealer said it was "normal,"
but I seem to notice it getting a bit more noticeable. Any suggestions?
No Jim, howling is not a normal condition for a Ford Explorer. ( why do dealers always use this excuse, I'll never understand ). Especially if your noise is becoming more pronounced I would start with basics first and inspect the tires. Be sure the tire pressure is correctly set. As a guide, use the tire manufacturer's cold pressure rating, which is on the side of each tire.
Tire cupping is a common event on these vehicles. If a tire is cupped it will be louder and can make a noise that would make one think that there is a bearing problem. Then rotate the tires and test drive the vehicle. If the noise moves then you know it is a tire problem and the rest of your vehicle is just fine.
Now if the howl remains unchanged after this then this may be the start of a problem that will require closer inspection.
Ford Taurus - Airbag light code 9
Ford Taurus
I have a 1990 Ford Taurus with an airbag light which is giving a code 9. I have been unable to discover the meaning of this code. The Ford dealer tells me that these US cars in the 1990s were a mixed up mess. Can you help with diagnosis and repair? I shall be listening to the show tonight at 11.00 pm on my computer for a hopeful answer.
Peter, my first question would be, have you had any work performed recently on the front of the vehicle? Like a radiator replacement for example. Why I am asking is the airbag code you're reporting is for an open in the circuit to the forward crash sensor. Other causes for an open circuit is a broken wire or an unplugged electrical connector. It is not uncommon to find a disturbed electrical connector problem after work has been performed. So if have had work done you should go back to the people who did the work and have them recheck their work.
Now if you've had no repairs recently performed and all the connections look good, then the circuits and the sensor have to be tested to determine the cause for the failure. If you are not skilled in this arena I would suggest keeping your hands off and allow a trained technician to perform the diagnosis and repairs.
Ford Ranger - 1994 Ford Ranger - reset button for the petrol pump
Ford Ranger
Hello Doc, I have a 1994 Ford Ranger pick up standard cab and it is a six cylinder. I cannot find the reset button for the petrol pump, can you advise me on this? Also I wanted to know if this will be all I have to do to get the pump working again?
Hi Nichole, It wont necessarily make your fuel pump start to work if by resetting the switch isn't the problem, but you have to start somewhere and that would be the first thing you have to eliminate from the many things that can cause a pump not to work.
Now on your vehicle it is normally on the passenger side floor where the carpet meets the firewall. Or it could be in the pass. side kick panel, on this panel should be a little access plate there which is marked, if there isn't one then it'll be on the floor area I have mentioned. Many times with the floor based unit people moving their feet around can unplug the wiring connector without realizing that.
Ford Taurus - Grinding noise from brakes
Ford Taurus
I have a 1997 Ford Taurus with 4 wheel disc brakes and I did my own brake job, replaced back rotors including pads. Now whenever I am braking there is a "grinding" noise like worn out brakes on the rotor. With the wheels off nothing was found, no scratches, scrapes, rust---what could it be, it's driving me bonkers?
It just may be the brake pad material. There are different grades of brake pad material and in most cause one would think that the better the grade the better the brake. But there is a trade off in some cases. Using a too aggressive semi-metallic brake pad on the rear of a vehicle of your type can result in a noise. Not a squeak or a squeal but a grinding type noise.
The fix is installing the brake pads from Ford/Mercury or an aftermarket that is low in metal content. But never install a brake pad that is not recommended by the manufacturer for the vehicle! Getting the right friction/braking material on the rear of your Ford should quiet things down. One should always put on the same pad as originally was fitted otherwise you are compromising the braking efficiency of the vehicle.
American model Ford Taurus - Battery light flickers
American model Ford Taurus
When starting my '96 American model Ford Taurus the battery light flickers then fades out. Is this an alternator or battery problem, or is it time for a tune up?
Cedric, Why the vehicle manufacturers persist in confusing the vehicle owner by mislabeling warning lights is beyond me. The vehicle manufacturers must be in cahoots with the battery manufacturers. That mislabeled battery light has sold more batteries needlessly than any other warning light I know of.
The battery light on vehicles has little to do with the battery; it's about the charging system. The warning light that is even more idiotic is the check engine light. I can assure you that if the check engine light comes on, your vehicle does have an engine, no one stole it! Now I could really get on my soapbox on this topic but it won't answer your question.
A flickering battery light is not an indicator that your car needs a tune-up...... As for the battery being the cause, that's not likely either. The battery warning light should be named "a charging system warning light " . And, with that little piece of information a consumer can logically conclude that if the warning light is doing strange things there may be a potential problem beginning with the charging system. A simple relabeling of the warning lights by people who use and drive the vehicles would minimize the confusion. But then I guess that's why they call them idiot lights after all. Because only an idiot would have given warning lights names like that in the first place.
Ford Taurus - Airbag dash light stays blinking
Ford Taurus
Dr. John I have just bought a used '91 Ford Taurus in good condition with 53,000 original miles on it. I am concerned that the Airbag dash light stays blinking all the time. What could it be? The car doesn't have an Owner'’s Manual.
That blinking Airbag light Mike is the Airbag computer's way of telling you that there is a system problem. Also, you should know that when the Airbag warning light is blinking/flashing the Airbag system is inoperative. The computer is flashing a diagnostic code. Counting the flashes allows a technician to refer to a diagnostic procedure to aid in diagnosing and repairing the system problem. A visit to your local repair facility should provide the answer and solution to the flashing Airbag light. Don't attempt doing anything yourself, air bag deployment is like dynamite, it only goes off once and can have dire consequences if your in the wrong place at the wrong time.
Ford Contour SE -
Ford Contour SE
9 months ago (30,000 miles ) I had the alternator on my 98 Ford Contour SE replaced with a rebuild. Recently, (at 40,000 miles ) the battery light started coming on immediately upon startup and stays on until I rev the engine. I replaced the original battery and the problem persists. I checked the battery voltage when the battery light is lit and the voltmeter reads 11.5V. After a quick rev to about 2,500 rpm, the light goes out and the voltage at battery terminals reads approx. 14.5V. Can you shed some light on what might be happening and why the problem appears to go away with a quick stab of the throttle? I would have thought that the light would come back on when the rpm's drop back to idle.
Clancy I'll just say...Replace that rebuilt alternator! The rebuilt you installed has a problem. If you let it go too long it will fail when you least need it to.
However there could be a problem as most rebuilt electrical stuff only comes with a 6 month warranty replacement, a few have a year warranty, hopefully you kept your bills so that you can check to see if you are still covered, if not, you'll need your wallet again.
Ford Probe - Ground Clearence
Ford Probe
I've purchased a 1996 'Ford Probe US model and noticed that it was designed with a front that is quite close to the ground. In this area there are fairly high granite curbs, and I see that I must be careful not to get close enough to allow these rugged stone curbs to tear up the front of my car. I have seen some vehicles that have had their bodies raised. This leads me to ask if it would be a sensible idea to have the front of my car raised a modest few inches?
Almost any vehicle can be elevated to a higher stature. but unfortunately, achieving a modest few inches in your vehicle is not easy. If you used larger tires; they would rub on the inner fender when going over bumps and the turning radius would be reduced because there's not enough room in the wheel opening to turn. Not to mention that the speedometer would have to be re-calibrated and the final drive in the transaxle would have to be changed to maintain performance, emissions and gas mileage. Altering the right height by merely one inch will cause accelerated tire wear and undesirable handling characteristics. By lifting the body Ford doesn't have a frame, per-se, it is constructed as a unibody. The frame is integral to the vehicle and there's no rubber mounts separating the two. There is no limit to a creative mind with some ingenuity, time and, oh-yes, a thick wallet, There are however many young people out there that have done modifications, so I suggest either talking with another owner who has successfully done this type of job, or go to one of the performance shops that sell bolt-on kits for doing various mods.
GMC Jimmy - Possible encoder failure
GMC Jimmy
I've got a '96 GMC Jimmy, I didn't use the 4WD much over the last year and when I tried to engage the 4WD, the HI light first flashed then did nothing so I tried the LOW and it did the same. It is now showing no response at all when pushing on either button and does not engage in 4WD. Any ideas on what I should have a mechanic look for to fix?
The most common problem we see with these systems is an encoder failure. This means the computer module that controls and monitors the 4WD shifting motor doesn't know where it is. The computer needs to know the location of the shifting motor to perform correctly. If the computer loses location information it stops responding. Diagnostic codes can be extracted but, because you have not used your 4WD much it may be all that you have to do is to clear the computer so it can start over.
Turn the ignition switch off and remove the fuse marked T-case (it should be a 20 amp fuse). Wait a minimum of 3 minutes then replace the fuse. Once the fuse is replaced turn the ignition switch on & off 5 times. Then start the engine and push the 4 Wheel HI button. If the system starts working, great. Be sure to exercise the 4WD system regularly to prevent a reoccurrence. If the problem returns then you need a technician familiar with your 4WD system to get into some diagnosis.
GMC Jimmy - Car has started to die whilst driving
GMC Jimmy
I have a 1992 GMC Jimmy with a 6 banger and the car has suddenly started to
die when driving. It will start and idle with a little two foot action.
Seems to be after it is warm. Has just started out of the blue. I have
changed the plugs,cap,rotor,pvc,and air cleaner. Any advise? The parts did
not solve issue.
Well you can either have a fuel pump ' flow and pressure ' testperformed by the garage, or firstly change the fuel filter. This could begetting plugged and the pump is trying to push the fuel through. It willusually run when cold due to an enriched mixture, and a slight fast idle.However when it is warm the mixture is a lot leaner and this is causing ittobe starved, because the pump can't deliver the fuel fast enough at thehigher road speeds. So it stalls.The other cause could be a problem with the fuel pump itself, being thatwhen you have been running a little while the fuel pump is heating up andthisis causing a drop in pressure to the injectors............ If a new fuelfilter doesn'tcure it, then you will need to have the pump checked for pressure and flow,when the engine is at normal operating temperature.
GMC Jimmy - Service light is always on.
GMC Jimmy
Dr. John I took my 96 GMC Jimmy to a local garage to have them diagnose why my service engine soon light is always on. Their tool came back with a 1406 diagnostic code. They told me I would need to take it to my dealer for service. Can you tell me what diagnostic code 1406 really means? The vehicle runs fine and gives no indication of any problems aside from the warning light.
A '96 GMC Jimmy with that code, I'm willing to bet you a coffee, that there is some carbon causing the EGR valve to stick open just a bit. There is a sensor on the EGR valve that reports the position of the valve to the computer. More often than not carbon deposits will cause the EGR valve to not close completely. The computer knows this because the voltage signal from the sensor on the EGR valve is not what it remembered it to be. As far as the computer is concerned if it isn't where it's suppose to be then there is a problem and the check engine light turns on. The fix is often just a cleaning. I would also suggest installing an aftermarket EGR gasket that has a screen to trap the carbon that causes this problem.
GMC Pick-up - Ignition timing help
GMC Pick-up
Doctor John, I need help to set the ignition timing on a '96 GMC Pick-up with a 4.3 litre engine. I had to take the intake off to fix a leak and I cannot get it to start.
Well Peter, Times have changed and setting ignition timing is one of those changes. It is not adjustable, the distributor in your vehicle is fixed and can only be installed one way and that is the correct way only. If you cannot start the vehicle the distributor is likely installed incorrectly. If you do get it started and the check engine light comes on you'll need to check the computer code. If a computer code # P1345 is present the computer has determined that the distributor is incorrectly installed. The computer knows this by comparing the sensor in the distributor, called a camshaft position sensor, to the crankshaft position sensor on the engine. If the two sensor's reference pulses are too far out of range from each other the engine will not start or if it does a check engine light will come on. Once you have the distributor installed correctly you need a computer scan tool to fine tune the distributor's sensor (camshaft) to the crankshaft position sensor. In the engine data display of the scan tool you'll need to find what is called camshaft retard.The camshaft retard indicates the difference between the camshaft position sensor and the crankshaft position sensor in degrees. I like seeing the setting within +or- 2 degrees of zero. Isn't amazing how complex something as simple as replacing a leaking gasket has become?
Jeep Grand Cherokee - The instrument panel not working!
Jeep Grand Cherokee
The instrument panel, along with my overhead diagnosis is not working on my '99 Jeep Grand Cherokee. When I disconnect the battery for a few hours, it all starts working normal, but after a few minutes to hours, it starts doing the same thing: all the gauges are dead.
The next time the dash display goes down on your Jeep don't disconnect the battery. Instead go to your Jeep dealer or a repair facility with the correct computer scan tools and have them perform a check of the Body Control Module (BCM). Because the instrument panel display and the overhead display are both going down it may be that the BCM has a problem. But getting into the system with a computer scan tool is critical. You'll want to know if there are any codes in the system that could be causing communication problems. If there are no codes present, then a function test can be performed via a scan tool. The function test allows the technician to command dash gauges and warning lights to cycle. BCM's do fail and replacements are costly. You'll want to be sure that there are no other system or connection problems before you replace the BCM.
Jeep Wagoneer - stalling
Jeep Wagoneer
I have a 1980 Jeep Wagoneer. I have changed the carb., fuel filter ect... but the stupid thing keeps stalling out. It seems to only do it when its been running hot or climbing up hills. What should I do?
First you need to prove that the problem is lack of fuel, before you spend any more money guessing.
The way to do that is to be prepared with a can of WD-40 spray, and the next time it dies on you, take the air cleaner off the top of the carburetor, and while a helper cranks the engine, give it a short squirt of WD-40 down the front barrel of the carburetor - if it starts, even if for only a second or so, you know your problem is lack of fuel. If it doesn't start, even momentarily, your problem could be lack of spark.
If it is lack of fuel, you are probably suffering from vapor lock - so you need to check the fuel pump output.
If you have or can borrow a fuel pressure gauge, check to see if the fuel pump is putting out at least 3 PSI at the carburetor input. If not, your fuel pump is failing. When you change the fuel pump, be SURE to change all the rubber hoses in the fuel system, including those back at the tank, because the modern fuel mixtures we have now are death on fuel pump and hoses - it eats the old rubber that was used up until a few years ago - that is probably what ruined your fuel pump also.
If that doesn't cure it, and it is still lack of fuel, you may have to add an electric fuel pump in series with the original type pump - and turn it on as a booster when you have fuel starvation problems. More and more as the gas gets worse, more and more cars are having to add electric pumps to keep going in hot weather.
Modern cars already have electric pumps, so they don't suffer this problem.
If the problem is not lack of fuel, you'll have to investigate the distibutor and all the wiring involved with it - especially the pickup coil in the distributor - they often fail only when it is hot, they will be OK when cold.
I hope this helps you figure out what is wrong,
Jeep Grand Cherokee - Petrol Gauge
Jeep Grand Cherokee
The petrol gauge on my '97 Jeep Grand Cherokee will drop to empty then return to 3/4 to 1/2 tank every so often or until I fill it up or the gauge goes below half tank. The dealer said I need a new pump but there isn't anything else going on. Any suggestions Doc?
Your vehicle is notorious for gas gauge problems Sal. In fact, there was a safety recall that affected about 400,000 Jeeps including the Jeep Grand Cherokee built in '97. The problem was the gas gauge would report that there was enough fuel when, in reality, there was not enough fuel and the vehicle would be dead on the side of the road. I'm not sure that your Jeep qualifies for this recall but it is worth checking into. Also, you're not being told the whole story.
If your Jeep dealer checks his/her Technical Service Bulletins (TSBs) they will find TSB# 08-19-97 that provides the part number for a replacement fuel sending unit that is sold separately. The TSB goes on to identify which of the 3 possible replacement part numbers that would fit your Jeep. The gas tank still has to be removed to service this part, but it is at a considerable savings to the vehicle owner compared to buying the complete fuel pump module. The fuel pump module is a new fuel pump and sending unit all together and is a bit on the pricey side. One last note, if your fuel pump has 100,000 miles on it and has not be replaced I would suggest installing the complete module. Any fuel pump with that kind of mileage is living on borrowed time.
Jeep Grand Cherokee - Pressure gauge falls
Jeep Grand Cherokee
The oil pressure gauge falls to zero and the 'Check Gauges' light comes on [along with a beep] every time I let off the accelerator on my '96 Jeep Grand Cherokee. When I accelerate, the gauge goes back to 30-40 psi. What's the problem and how much is the fix?
The first thing you have to do Kenny is a have a mechanical oil pressure gauge installed to confirm that the electronic gauge or sensor is not failing. I have seen bad oil pressure sensors cause total panic by providing misleading information. If the mechanical oil pressure gauge confirms that you do have a low oil pressure problem the oil pan will have to be removed to inspect the oil pump and possibly the engine bearings. A worn oil pump or leaking pick-up tube can cause the problem you're describing. A replacement oil pump is not too bad of a job. If it turns out that the engine bearings are worn you'll be looking at a rebuilt or replacement engine.
Jeep Cherokee - Problem with the choke
Jeep Cherokee
Dr. John I enjoy your listening to your show on broadband. I have a 1986 Jeep Cherokee with a 2.8 liter V6. I think I have a problem with the choke.
When the engine is cold it starts up easy, real easy. But when it's hot, I have a hard time starting it. To get it started, I have to hold the gas pedal to the floor.
Do you think the choke is in a closed position when the engine is hot? If so, should I have the mechanic adjust it?
No adjustment necessary! The problem you're describing is common. It's likely that the electric choke heating element is not operating. The most prevalent reason is due to corrosion on the electrical connector at the choke itself. Usually the connections can be cleaned, but in some cases the corrosion will be so bad that the connector and the electric choke assembly will have to be replaced. Glad you enjoy the show on your pc.
Jeep Grand Cherokee - Brakes act strange
Jeep Grand Cherokee
I changed the ball joints on my '97 Jeep Grand Cherokee 4 wheel drive. Now my brakes act strange. It seems my ABS is acting up and I hear a clicking sound as I increase in speed.When I apply the brakes it sounds like my brakes are ratcheting.
Take a look at the front axles of your jeep just where they enter the hub assembly. You should see a part that looks like a gear that is mounted on the axle. That gear is called a toner ring. As the teeth/gear looking part of the toner ring pass by the wheel speed sensor, a signal is created that the ABS system uses to monitor wheel speed. If a tooth is broken off the gear, the ABS computer will think that the wheel is turning at a different speed. This will cause the ABS computer to become active when it doesn't have to be. It doesn't take much to mess up the toner ring or even the sensor. I would suggest a close inspection of these components on both sides of the vehicle for possible damage. Any signs of damage will require replacement of the sensor, or if the toner ring is damaged the axle will have to be replaced. The toner ring is not sold separately.
Lincoln Mark VII - Parking brake problems
Lincoln Mark VII
Doctor, I own a 1988 Lincoln Mark VII and my “ automatic parking brake release †is not automatically releasing (like to use it) – I have to reach under the dash and use the manual release. I also noticed my cruise control is not functioning either. I understand (from the owners manual) that these are both vacuum operated. My question is: Do you think these two problems are related, and is there anything I can do to remedy it?
Well Frederick It is true that both components do require engine vacuum to operate. Due to the age of your vehicle it is very likely that the vacuum hoses in the engine compartment are hard and most likely cracked. This would cause a loss of vacuum supply to these components. Even though your vehicle is not known for great gas (petrol) mileage, fixing a vacuum leak that is effecting the cruise control and emergency brake release will make the engine run better and improve mileage
Lincoln Continental - Ignition coils breaking down
Lincoln Continental
Dr.John, I own a '99 Lincoln Continental, I believe that one or more of the ignition coils are breaking down but I don't know how to tell which one(s). I used a multimeter to check them against a known good (new) one but the readings are all very close. How do I isolate the bad one
The easiest way Roland is to connect a computer scan tool to the computer and watch the misfire monitor information from the computer. Now each time a cylinder misfires the computer makes a note of it. It's a real fast way to pin down which cylinder has the problem. If the ignition coil is acting up enough the computer will turn on the check engine light and there will be a diagnostic trouble code in the computer that will flag the offending cylinder. There are other means, but if you don't know what you're doing you can get yourself in trouble pretty quick.
Lincoln Town Car - Computer driven dash board problem
Lincoln Town Car
Two years ago, the computer driven dash board display, in my '90 Lincoln Town Car, started to act up. It started with the outside temperature display which was okay for about 20 minutes and then suddenly would drop to 38 degrees below and stay there. I had a sensor replaced and drove the car for about 10 minutes and it did the same thing. I was told that the display needed to be replaced or it would go dark in about three months. It still has not gone dark, however, during this two-year period the "door ajar" warning lights up and stays on, also the "air bag" warning lights up and blinks. The average petrol mileage, miles traveled and miles left have all become erratic.
Last month the speedometer would stop working then drop-down, back up and then would wind up at 0. It would suddenly start working again into the same thing. The dash display for fuel and temperature are still working. When I fill the tank now it registers full on the petrol gauge but the miles left to empty which use to register about 400 miles now registers erratically. Could it be a sensor or module?
It's possible that your digital dash may have to be replaced. You want to have some other items checked first. For example, the signal for the speedometer is created by a signal generator mounted in the transmission. It's not uncommon for these signal generators to fail, resulting in erratic m.p.h. reading. The computer also relies on the speedometer signal to calculate average gas mileage, miles traveled, etc.. Has anyone asked the air bag computer if there is a problem? The warning light is supposed to come on when there's a system problem. The digital dash relies on information from other components. Verify the quality of the information the digital dash is receiving before replacing it.
Mercury Sable - Steering Locks in Wet!
Mercury Sable
I am a 60-year-old widow with a '98 Mercury Sable. If the weather is raining or wet, I am afraid to drive the car. I will start the car, pull from the driveway, and go down the wet road. I can be going straight or attempt to turn. The steering begins to lock up, the car almost goes dead, the engine light comes on and something squeals. The steering is so tight I can hardly steer (engine dying I guess). The brakes make noise also. I thought maybe it was the brakes. Now I think maybe the transmission. All I know is that it is a very dangerous situation. I have had the dealership look at it, plus two other places. Of course, it doesn't show up for them. I'm a prisoner in my home on rainy days.
I would first suggest an inspection of the automatic belt tensioner and here's my reasoning. The squeal you mentioned along with a loss of power steering may indicate that the serpentine/fan belt is slipping. It is not uncommon for the automatic belt tensioner to stick due to corrosion and rust. When this happens the tension on the belt is not held correctly. Why would rainy days be a factor? The rain/moisture can get on the belt and pulleys and cause the belt to slip. When the belt slips the power steering will become stiff and hard to turn, a belt squeal could occur as well as the belt tries to drive the power steering pump, alternator, A/C compressor, etc.. If the belt slips enough it can cause the alternator to stop charging resulting in a dash warning light being illuminated. Also beware of the human factor. Serpentine belts come in many sizes. If the belt has been replaced it is possible that it is the wrong size. It only takes a belt that is a little larger/longer to cause the automatic tensioner to be out of its range of control, resulting in slippage.
Mercury Grand Marquis - High Idle Problem
Mercury Grand Marquis
Now that the temperatures are dropping my '91 Mercury Grand Marquis is having an idle problem. At temperatures below 5 degrees (C) the engine will race when I try to slow down. The engine will start and run normal until sometime after it's been driven at least 10 minutes. It will then start racing at a very high RPM and will not go down. The engine must be shut down for a few minutes for it to return to normal, only to repeat the problem. All the usual culprits have been replaced including the throttle position sensor, air sensor, and temp sensor. Any ideas?...."ll be listening to your show on the pc tonight.
Andrew, What has to be determined is if the idle problem is a command or mechanical problem. A command problem is the computer deciding the desired idle speed. If it is a command problem then it can be isolated rather quickly. Have your technician show you where the Idle Air Control (IAC) motor is located and how to electrically unplug it. When the condition occurs, unplug the IAC motor's electrical connector. If the idle drops then you have a command problem. If it doesn't you may have a sticking IAC motor. The fix for a sticking IAC motor is a cleaning or replacement. Most of the time I've found that a problem like yours lays with the IAC motor needing a darn good clean.
Mercury Grand Marquis - Brake problems
Mercury Grand Marquis
Doctor John, I have an ‘85 Mercury Grand Marquis, great car but I’m losing brake fluid. The area around the master cylinder looks stained. Does it sound like the master cylinder needs replacing? If so what would it cost?....
I would not recommend replacing the master cylinder Ray without a thorough brake inspection. Why? Your vehicle is old enough to easily have problems with the hydraulic wheel cylinders for the rear brakes. The bottom line is, that when there is a braking system problem all 4 brakes should be inspected. Rarely is there danger in a vehicle that won’t start, but things can sure get interesting if a vehicle wont stop. Have your technician inspect the condition of the brakes at all 4 wheels then perform the needed repairs.
Mercury Grand Marquis - Idle problem
Mercury Grand Marquis
For the second winter now my ‘91 Mercury Grand Marquis has had an idle problem. At temperatures below 5 degrees (C) the engine will race when I try to slow down. The engine will start and run normal until sometime after it's been driven at least 10 minutes. It will then start racing at a very high RPM and will not go down. The engine must be shut down for a few minutes for it to return to normal, only to repeat the problem. All the usual culprits have been replaced including the throttle position sensor, air sensor, and temp sensor. Any ideas?
What has to be determined Andrew is if the idle problem is a command or mechanical problem.
A command problem is the computer deciding the desired idle speed. If it is a command problem then it can be isolated rather quickly. Have your technician show you where the (IAC) Idle Air Control - motor is located and how to electrically unplug it. When the condition occurs, unplug the IAC motor’s electrical connector. If the idle drops then you have a command problem.
If it doesn’t you may have a sticking IAC motor. The fix for a sticking IAC motor is a cleaning or replacement. Most of the time I’ve found that a problem like yours lays with that IAC motor.
Mustang GT - cooling problem - 95 Mustang GT cooling problem
Mustang GT - cooling problem
Hi Dr. John, Love the informative show, now my problem with my '95 Mustang GT is that I have a cooling problem for a few months. The car will slowly overheat at a standstill. The fan will come on but sometimes it doesn't seem to cool the car enough and it will soon overheat. When I'm driving the car it actually runs too cold and never gets into the normal range. Being that it is now wintertime it's not too bad but when warmer weather gets here I probably won't be able to drive the car. I have changed the thermostat, flushed and refilled the radiator and changed the belt, but to no avail. I've been racking my brain for months, any ideas doc?
A closer inspection of the water pump and cooling fan is in order Bill. Water pumps have impellers that can wear in a manner that reduces coolant flow at the lower engine speeds of in-town driving and stop and go traffic.
At highway speed the engine drives the water pump fast enough to cover the problem, and the incresed air flow through speed also helps. As for the cooling fan, just because it turns on doesn't mean it's doing its job. As an electric cooling fan motor wears it can lose speed/RPM. The reduced speed means less airflow over the radiator to cool the coolant. Also the cycling of the fan will have to be checked to see if that is correct in coming on and off.
Oldsmobile Ciera Wagon - Stalling problems
Oldsmobile Ciera Wagon
I own a ‘95 Oldsmobile Ciera Wagon with low mileage of 23,000 miles, It runs great around town. After going on the motorway for an hour or so, the car stalled on the exit ramp. Coming home , the car stalled again. The dealership checked the sensors, all checking out ok. My personal mechanic checked and found everything being ok. Any ideas? I even asked our priest for help!
Ask your mechanic to temporarily disconnect the lock-up torque converter for the automatic transmission. Then go drive the vehicle on the highway for a while and see if the stalling problem still happens when you stop at the exit. I'll bet you a cup of tea the problem will not occur. If I'm right, have your mechanic replace the solenoid for the lock-up torque converter. The solenoid has a valve in it that is known for sticking and causing stalling problems under the driving condition you're describing. Your vehicle is of the right vintage to suffer from this problem.
Olds Delta 88 - Blower motor will not stop running
Olds Delta 88
I have a 1990 Olds Delta 88 with electronic climate control. The blower motor will not stop running when I use the off button and when I turn the ignition off it continues to run. I got under the bonnet and unplugged it. What could be the cause of this?
Jerry, It sounds as if there is a problem with the blower control module. The blower control module, AKA computer, takes information from the heater and A/C control assembly (the display with the buttons to push) and translates that information into electrical power to the blower/heater motor. Why doesn't the blower turn off with the ignition switch? The blower control module has battery power to it at all times. A replacement blower control module may be in your future. Good Luck!
Bravada Oldsmobile - Fire under passenger seat
Bravada Oldsmobile
What can cause a fire to occur under the passenger seat of a 1997 Bravada Oldsmobile?
Did the fire start under the seat in the carpeting by any chance? If so I would be inspecting the running condition of the engine. Why the engine? The catalytic converter is located under the passenger side seat. If the engine is running poorly the converter will overheat.
If conditions are right the converter can become so hot that it will cause the flooring/carpeting in the vehicle to ignite and burn. I have seen this condition occur in other vehicles as well. Just one of those little reasons that a rough running engine and/or check engine light should not be ignored.
The other possible cause could be if it is an electric seat or has a seat warmer then there could be an electrical problem that caused the fire.
Oldsmobile Bravada - Cylinder plug
Oldsmobile Bravada
I was changing the spark plugs in my 1999 Oldsmobile Bravada and the #3 cylinder plug is virtually impossible to get a socket on. The steering column runs directly in front of the plug and the heat shield around the plug, making the plug inaccessible. Can you tell me how to get this plug changed? Is there a special spanner or socket that I need?
Isn't that design some kind of fun or what? There may be a socket out there that is made just for that tight fit problem on # 3 cylinder, but I made up my own Look for a spark plug socket that has a hex head (looks like a nut) on the top of the socket and it needs to be a short spark plug socket as well. You can just sneak it by and get it on to the spark plug. Then use a wrench on the socket to break the spark plug loose. If you find the right wobble extension for your hand ratchet you can get right on it and spin it right out. Use care when installing that spark plug. I've repaired the damage of those who take the bull in a china shop approach. If you're taking the time to save the money, then be sure to take the time to do it right.
Oldsmobile Cutlass - blue smoke
Oldsmobile Cutlass
I have a 1999 Oldsmobile Cutlass mileage is 120,000 miles. I re-gasketed a previously owned engine and put it in my car. I was travelling roughly at 65-70 mph when the car lacked all power and gave the car behind me a blue smoke bath. I pulled over at that time and checked the #4 spark plug and it was coated with oil. At that moment I thought my valve seals needed replacing. I towed the car home, opened the engine up, and found that along with valve seals the #1 exhaust valve had a pie slice hole in it. In addition, the #4 piston had a hole in the top of it. I am not a mechanic but I think though I may be wrong that the spark plugs that I was using were at the wrong heat range. I was using AC Delco's rapid-fire. Can you tell me why there was a hole in the piston and why there was a hole in the valve, I would be very grateful for your information.
The problems with the exhaust valve and the failed piston are probably due to that cylinder running lean. Check the fuel injector for that cylinder and also look for vacuum leaks that would affect that cylinder. I do not think the wrong heat range of spark plugs would cause the problem you describe.
Olds Delta -
Olds Delta
I have set the firing order right after I replaced the Cap & Rotor in the midst of doing a tune up. Car started
before the tune up. Now? Nothing! I know the firing order, I am pretty sure the driver side bank is odd and
the passsenger is even. Any suggestions?
Yes, you seem to have the firing order and the cylinder numbering correct, but just to review for others that might be listening to us, the firing order is 1-8-4-3-6-5-7-2, and the cylinders are numbered 1-3-5-7 front to rear on the driver's side, and 2-4-6-8 on the passenger side, front to rear.
Next, you need to check that the plug wires start out at the correct hole in the cap, and progress around in the correct direction of rotation.
To check this, make a note of where the #1 plug wire plugs into the cap, and then take the cap off. Next, rotate the engine until the timing mark on the crank pulley lines up with the TDC timing mark. Now, look at the rotor - is it pointed at #1 plug wire's location? If it is not, see if it is pointed at #6's location (exactly opposite the #1 position.) It should be at one or the other of those positions.
Also, note the direction of rotation of the rotor when you crank the starter, and make sure that you have installed the plug wires in order using that same direction of rotation.
Also, if you have had the distributor out of the engine, there is a chance you do not have the distributor back in so that it is timed right. As you may be aware, the crankshaft goes around twice for each rotation of the distributor, so there is a 50-50 chance of getting the distributor back in 180 degrees out of time. I'll assume you did not remove the distributor from the engine, but if you did, post a follow up question to me and I'll help you get it all back right again.
If you complete all what I am telling you and it still won't run, there is some other problem and we'll have to do some more detective work, but there are so many possiblities I could stay here all night talking and still not hit on the right one!SO, get back to me if that doesn't clear it up for you.
Plymouth Acclaim - Smoking Tailpipe
Plymouth Acclaim
Generally if the valve seals are failing you will get a cloud of smoke (blue in color) out the exhaust on start-up. But, this cloud will clear up quickly if it is valve seal related.
Note: There are some engine designs that this does not hold true. But, I’m comfortable in your case to say that it is NOT valve seal related.
Your vehicle’s engine is smoking out the exhaust on start-up and continues to until the engine reaches a certain temperature. I would be inclined to believe that the oil control and/or scraper rings on the pistons are failing. When the piston rings that control oil loss fail, the volume of smoke out the exhaust is from noticeable to quite remarkable as the engine is warming. Once the engine is to operating temperature there may be no detectable smoke whatsoever out the exhaust. I would suggest having an engine specialist check into your problem for the needed repairs.
Generally if the valve seals are failing you will get a cloud of smoke (blue in color) out the exhaust on start-up. But, this cloud will clear up quickly if it is valve seal related.
Note: There are some engine designs that this does not hold true. But, I’m comfortable in your case to say that it is NOT valve seal related.
Your vehicle’s engine is smoking out the exhaust on start-up and continues to until the engine reaches a certain temperature. I would be inclined to believe that the oil control and/or scraper rings on the pistons are failing. When the piston rings that control oil loss fail, the volume of smoke out the exhaust is from noticeable to quite remarkable as the engine is warming. Once the engine is to operating temperature there may be no detectable smoke whatsoever out the exhaust. I would suggest having an engine specialist check into your problem for the needed repairs.
Plymouth Sundance - Fuel Consumption
Plymouth Sundance
I've just bought a '90 Plymouth Sundance which runs perfectly (engine very smooth with plenty of power) but only gets 20 mpg. It has a 4 cyl - 2.5 litre engine with 3 speed automatic. If the O2 sensor fails to generate its 1 volt signal, could it cause a rich fuel mixture - without affecting driveability?
Roland, an O2 sensor can fail in a manner that will cause poor gas mileage. But, before installing any new parts I suggest checking the basics. It's not uncommon for the vacuum hose to the Manifold Absolute Pressure (MAP) sensor to crack, collapse or become restricted. Now MAP is a fancy name for an electronic vacuum gauge that the vehicle's computer can read. The vehicle's computer makes fuel delivery adjustments based on the information it receives from the MAP sensor.
The computer is completely clueless that the information it's received is incorrect. The result can be increased fuel consumption with no noticeable driveabilty problems. It's important to be sure the basics are correct before replacing any pricey computer parts. You can waste a lot of money guessing.
Thanks for the question Roland
Plymouth Voyager - Body control module
Plymouth Voyager
Dr. John, I have been told that my ‘98 Plymouth Voyager needs a body control module. I have no working gauges, tach. or speedometer. The LED readouts for the odometer and gear selector only show half a display. They also remain lit when the key is turned off. This problem is not constant, sometimes things work normally. You answered another person some time back by saying to be sure that the vehicle really needed a BCM and not a new dash display. How can I be sure of what I need as parts here have to be ordered and are expensive, so I have to be sure?
Now there is good reason to be concerned, because Body Control Module (BCM) is not cheap and it cannot be returned after it has been installed. There is a diagnostic procedure that allows a technician to determine if the BCM is the problem or not. The problem with diagnosing a BCM is that you have to have a computer scan tool to communicate with and perform function test to the BCM. You did provide a good piece of information. The fact that part of the dash display stays active even after the vehicle is turned off is a good indicator that the BCM has lost touch with the rest of the vehicle and is wandering around in its own little world. But before paying the bucks I’d pay to be sure you’re replacing the right part.Good Luck!
Plymouth Voyager - Air bag warning light
Plymouth Voyager
Hello Doctor John, My problem I have with my 1997 Plymouth Voyager van is more of a nuisance thing. I have my air bag warning light on continuously, I have had the system checked out at the dealership and they tell me there is absolutely nothing wrong that they can see or find, and that I should live with it! I find this very hard to believe and I think they're just not trying hard enough. There must be a problem somewhere otherwise why would the light be on, I though a warning light is meant to tell you there is a problem?
Lawrence, there is a problem for sure! If the light stays on all the time it means that the ABS system is disabled but your normal power braking system is working fine as long as it has been maintained regularly. I suspect that water has found it's way into the airbag's 6 way connector and has started to cause corrosion. This will certainly keep the light on all the time you are driving. Go back to the dealership and ask them to check the 6 way airbag connector. being as this is located under the drivers seat, with getting in the vehicle with wet shoes on many occasions causes the water to saturate the carpet and find it's way into the connector.
Plymouth Sundance - Crunching sound on steering turn
Plymouth Sundance
I have a very annoying noise in my 1993 Pontiac Sunbird. What happens is that every time I turn the steering wheel to the right I get this horrible crunching sound. I have been to the garage and had the front end checked out and had everything sprayed that could cause this noise, but I still have it, any suggestions?
I have repaired four Sunbirds with the exact same problem. I think I can safely say that what you need to do to have this alleviated is a new steering grommet on the right side. Once this is replaced no more crunching.
Plymouth Breeze - Brakes
Plymouth Breeze
I drive a ‘98 Plymouth Breeze. About 3 weeks ago, I changed my brake pads and turned the disc rotors. The old right front pads were worn in slopes (to interlocking triangles). The brakes also made a clicking noise on that right side. The left was worn normal. Have you ever heard of this before?
The wear problem you’re describing is commonly caused by binding or worn brake components. The most common problem is corrosion and rust. This causes the brake pads to rust and bind in the holders or the brake calipers not to slide freely.
The clicking noise you mentioned is a good indicator that a component of the braking system was binding. You were hearing the snap as it was being forced to move. Brake components must be clean, lubed and move freely. If you’re still hearing a click or braking related noise after you performed the brake service, you had better inspect the system more closely. Replace any worn alignment pins or parts that look suspect.
Plymouth Voyager van - Stalling
Plymouth Voyager van
Dr. John I have a 1996 Plymouth Voyager van with 184000 kms on her and it just recently started to stall when you slow to an idle at a stop sign etc or backing up. When travelling down the road there is no problem as of yet. I have tried gas line antifreze and premium gas with no avail.
Hi JW! Well this could be many things, I am going to list some of them and also the most common one that causes this problem 99% of the time.
- CTS ( coolant temperature sensor )
- Temperature sensor/switch
- TPS ( throttle position sensor )
- IAC ( Idle air control) valve
- ISC ( Idle speed control ) actuator
- EGR ( exhaust gas recirculation ) valve.
Now all of these are normally checked out by having the garage perform a " fault code review " so that the technician can read all the sensors and find out if they are or aren't working within their normal parameters. Now with the IAC valve this could very well just want cleaning. Plus while that is being done the throttle plate should also be cleaned as this gets varnished up as bad as the IAC valve.
With that amount of mileage on the vehicle, have you ever had the injectors cleaned with a ' Motorvac ' unit of similar machine? If not then this could also be a source for stalling.
Plymouth Voyager - Gearing Problems
Plymouth Voyager
Doc I have a 91 Plymouth Voyager 80,000 mi, with a four speed computer controlled transmission. Recently, while decelerating from highway speed, it will suddenly shift down into 2nd gear and stay there until the ignition is shutoff after which it performs normally, until the next situation. I have been told that there is a rather simple solution for this problem. Do you have any information you could share?
Is seems as if your transmission (with a mind of its own) is going into fail/safe or limp in mode; I call them the survival modes. In the event that the computer or sensors for a computerized transmission fail, the transmission will go into a survival mode. The survival mode allows the vehicle to be driven, but with limited abilities. This permits the driver and passengers to continue safely to a repair facility. The survival mode in your vehicle just happens to be second gear.
A commonly seen cause is due to loose electrical connectors at the transmission. Your vehicle’s computer will likely have stored information, trouble codes, related to your problem. A qualified technician would have no problem accessing the computer for this information and identifying the cause of your shifting problem.
Plymouth Breeze - Frozen Boot lock
Plymouth Breeze
Doctor I have a '99 Plymouth Breeze and the boot lock is frozen, probably with rust. I tried WD40, and graphite. How can I remove it and replace it?
Mike, I haven't seen any rusted trunk latches on vehicles of your type. I'm thinking that you could have a latch which is broken or you've gotten something stuck in it when the trunk was closed, which is the most common problem I have seen.
Now to unbolt the trunk latch you will have to remove the back seat and reach into the trunk with a long extension to unbolt the latch. You may need the use of a trouble light to see by. The extension you need isn't in your normal do it yourself socket sets. Once you get the seat removed you can determine what extension you need to buy or go to your local repair facility and have them unbolt the latch for you.
Pontiac Sunbird 2.0L - squeaking under the hood
Pontiac Sunbird 2.0L
I have a 1991 Pontiac Sunbird 2.0L. I noticed a squeaking under the hood when the car was cranked and was told that maybe it could be the brushes on my starter. When my starter finally gave up, I had it rebuilt and the squeaking was still there. I finally had it diagnosed and was told I needed a belt tensioner (the pulley). So I went to every parts store around and there are two pulleys listed for my car. The tensioner pulley and the idler pulley, but the problem with these two pulleys are, they are too wide. If I were too put one on, they rub against the vailance in my car and are just much too wide. I had to go to Pontiac and order the whole tensioner. What I don't understand is why the two pulleys that the parts stores list for my car are much too wide. How can this be?
Hi TheGoodbyeGirl! I don't know who told you it could be brushes squeaking in the starter motor, that is a new one I have to add to my cranky diagnosis list. Carbon brushes on copper don't squeak. But if they are worn down to the metal brush holder you will get a whistling sound but also the starter motor wont work. All it needed was someone with a mechanics stethoscope or a long shafted screwdriver ( which acts like a stethoscope ) to pin-point the noise and save you wasting your money. Unfortunately that didn't happen.
As for the pulley's, obviously if they touch anything anywhere they have to be the wrong replacement, and this sometimes happens with what we call ' after market ' made replacement parts. Now I don't know whether you are talking about a pulley that has the ' V ' shaped belt and you were shown the serpentine belt type pulley, or the fact that you do have the serpentine ribbed pulley but what they had shown you were the wider ribbed pulley's which I suspect they did.
Unfortunately with dealer parts though they will be a correct fit you have to buy the complete unit. I suspect the auto parts store you went to may well have been looking up the wrong year, engine size or even the model. Perhaps it was a Sunfire they looked up.
At least you have the problem taken care of though it cost you a learning curve.......always get a second opinion on anything you take the car in for, except your regular oil changes. Another thing to remember also is always ask for your old parts back when a problem part has been replaced.
Garages are suppose to ask you this but too many don't so it'll be up to you to ask. The reason for getting parts back is that if after a day or two the noise or problem comes back, you know the part they told you was the problem obviously wasn't. So your able to take the 'old' part back and complain. If you have to take these people to small claims court, you still have the evidence which the garage would have thrown away after you left.
Pontiac Trans-am - Wiring issues in the engine bay
Pontiac Trans-am
Hello Doctor, My question is with my 1990 Pontiac Trans-am. I am currently ‘ tarting ‘ up the
engine in it with after market dress-up accessories. One of the things I want to do is to run the
spark plug wires on each side through a chrome tube. Which should keep them neat and tidy.
My question is are there any drawbacks or problems I should be aware of in doing this?
A very good question Sidney, and one I am sure a lot of customizers may well learn from myanswer.Any two ignition wires let alone 4 each side that run touching each other for over 6 inches willcause problems. the voltage and current in the active wire can build up sufficient voltage in theadjoining passive wire to actually cause an arc-over in what was supposed to be a passive sparkplug. Now if at that instant the passive plug was in a cylinder full of active air/fuel mixture andthe piston was, we’ll say 60 degrees before TDC ( top dead center ). Wow, Look out!!! You’dhave detonation city and maybe you’ll end up with a piston down in the oil pan.That’s why vehicle manufacturers usually have wire looms that keep the wires at least a 1/4â€apart. If you notice on your wires at the moment that is exactly how they are in the loom. SoSidney what you would like to do is a big NO! NO! And I can’t say that loud enough.What I suggest you do if you still want a nice chrome look to the harness. is to purchase somechrome plastic tubing, slightly larger in diameter than the wire itself, they should be 8 mmsilicone wires you have on there, run each spark plug wire individually through each plastic tube,they will look just as aesthetically pleasing to you with no headaches attached.Thanks for the question Sidney and good luck on your project.
Pontiac Catalina - Heating problems
Pontiac Catalina
Hello Doctor John, I have a problem with getting any heat on my Pontiac Catalina, I have sort of checked most things I know about but nothing seems to alleviate the problem can you help me?
Most heating system problems can be traced back to one of the
following;
- Failed Thermostat
- Failed heater shut-off valve
- Lack of coolant
- Lack of pressure
- Plugged heater core.
Generally, coolant leaks are quite visible to the owner and this may in fact be the first indication that a problem exists. Any time the coolant level gets low, the heated air coming into the interior of the vehicle becomes luke warm or even cold. In the case of a gradual leak in a heater core, which wouldn't be visible to you, two symptoms may indicate a problem: window fogging, indicating excessive moisture in the incoming air; and a
sweet sickly smell inside the car ( from the glycol in the coolant. )
Or if the heater control shut-off valve is rusted closed so that when you operate the cable control for heat or press the vacuum operated button, it doesn't open the valve to allow coolant to flow through the heater core.
If you find that none of these things are evident and you are still losing coolant then you must look for at an internal leak. To do this test you can either have a 'dye ' test in the radiator or litmus paper test to determine if you have any carbon monoxide or hydrocarbons evident in the coolant. If there is then this indicates you have either a cracked engine block or as in most cases a cracked or corroded head gasket.
Good Luck!
Pontiac Trans Am - Interior lights Problem
Pontiac Trans Am
My name is Daniel and I have a 1976 Pontiac Trans Am. Recently my interior lights(dome and the under dash lights) have been illuminating when i press the brake pedal, consequently the brake lights have stopped working. When the doors are opened the dome light does not come on at all, but the lights under the dash do. Also if a door is opened the light in trunk wont come on, but if the doors are closed it will come on. Using the headlights doesnt change any of these factors except the rear running ligths come on, yet the brakes still dont illuminate. I hope you can help me with my annoying dillema
Thanks, Daniel
Hi Daniel! Have you disconnected the brake light plug from the switch on the brake pedal, if not do so, and see if the same problem persists. If it doesn't then there is a problem with the wiring on the brake light switch, or headlamp switch, or to the harness to the rear brake lights.
If the problem still persists with the brake light plug disconnected, then there could be a problem at the fuse block, or the headlight switch itself. Though the headlights are part of the operation of the headlight switch, they are on a separate circuit but the switch itself controls the park lights, interior light and rheostat ( dim and brighten sequence ) . There are also terminals on this which give the 'live ' feed to other circuits and the the brake light switch, so it could be that the headlight switch is faulty.
If you have a wiring manual fine, but if you don't and have limited knowledge about wiring color codes and harness routing, then I suggest you get the experts in this field by taking it to an automotive electrical shop. Remember if you happen to cause a car fire, your insurance can null and void your claim, with a bona fide shop they are covered by insurance for any mishaps.
Pontiac Sunbird - Electrical problems
Pontiac Sunbird
1993 Pontiac Sunbird 4 Cyl mileage: 107,000 miles. My car has daylight running lights. Recently these lights have been going on and off. I checked the fuse and it was alright. And there doesn't appear to be any other problems in the electrical system. Any suggestions?
Hi Allison! Electrical problems are really difficult to trace. In your case, I would wait for the running lights to fail and then do a 12-volt power check to the wiring circuit for the running lights. However the most common cause for these to act up is the daytime running light module which is under the hood ( bonnet ). This is located on the inside fender panel ( wing ) on the drivers side, check that the plug and connections aren't corroded. This could be giving an intermittent ground ( earth ) problem, try cleaning first. If the problem still persists then possibly the plug or the module, or both may have to be changed.
Pontiac 6000 Sport - Fuel starting running problems
Pontiac 6000 Sport
Help! Our '88 Pontiac 6000 just stopped dead three weeks ago, the problem seems to be it's not injecting petrol. I have replaced the ECM, MAP sensor, fuel injector,(it is a TBI model), checked the TPS and O2 sensor voltage and I've jiggled wires all over the car to see if it was shorting, no luck. Now I'm about to go bonkers!!!. The only thing left to replace is the ignition module, but we have spark. If I pour petrol down the bore it fires up straight away! What could it be ?
If the engine starts when you add fuel then you have to ask why no fuel? Is there good fuel pressure? The fuel pressure on your vehicle's injection system has to be in the area of 12 PSI. If fuel pressure is correct then you have to check to see if the fuel injector is being triggered by the computer.
If the computer is not triggering the injector you have to find out if it is receiving a signal from the ignition module. On your vehicle you can have spark with no signal to the computer to operate the injector. Without the right tools and information, diagnosing this problem is a hit or miss event. By what you tell me your check book has taken a few direct hits.
Take it into your dealer or a good garage that specialises in troubleshooting and have them run a scan on the system.
Pontiac Parisienne - Engine idles too fast
Pontiac Parisienne
I have an 1986 Pontiac Parisienne, my problem is that whenever I start my car the engine idles too fast. One petrol station technician told me I need a rebuilt carb; my brother says they are wrong. He says the carb looks good; my question is how do I know if it does need a rebuilt carb? I don't mind paying, I just don't want to be taken in either! Most places see a female and pound signs go up in front of their eyes! Please help, I'm tired of the run around.
Trust your instincts; you seem to be uncomfortable with the gas station diagnosis. (Nothing against your brother but, "looks aren't everything".) High idle problems can be caused by misadjustment, sticking linkage or worn components. Also, be aware that there are external factors, (not the carburetor's fault) that can cause a high idle condition on your vehicle. If I'm not mistaken, a rebuilt carburetor for your vehicle is over 400 pounds sterling and a brand new one is over 700 pounds. This is a lot of money to spend on a 12 year old car. If you're spending this much money, you want to be assured that a replacement carburetor will correct the problem. You don't want to hear someone saying, "I think this will fix the problem". I would suggest getting a second opinion from a qualified technician on the cause of your high idle complaint. You want a repair facility that is willing to stand behind, and in front, of their diagnostics and repairs.
Pontiac Grand AM - Leaking coolant
Pontiac Grand AM
Doctor John, I was changing the oil in my 2001 Pontiac Grand AM and noticed coolant in the engine oil. Since I bought the car (new) I would lose coolant and get the low coolant alarm. It had stopped for a while until about two weeks ago, I got the low coolant alarm and filled it again. I suspect it had a small leak when I first bought the car. The warranty is now well expired. I checked several web sites on information on recalls of leaking coolant in '01 Grand AM Pontiacs but only found one case. Do you know of any other cases?
I'll bet a coffee that your Grand AM just happens to have a V-6 engine. That engine is known for intake manifold gasket problems. The problem with the gasket? It allows coolant to leak inside the engine. This causes 2 problems; 1. A coolant leak that no one can see. 2. Only a drop of anti-freeze in the right place will cause untold engine damage. I would suggest not running the engine on your vehicle until the source of the coolant leak is found that is allowing anti-freeze to enter your engine oil. My bet is on the intake manifold gasket. Immediately check with a GM dealer they may do something on their 'goodwill program Simone.
Pontiac Gran Prix - Problem head lights
Pontiac Gran Prix
Doctor John You have helped me out before so this time it's trouble with my 2000 Pontiac Gran Prix. When I turn on my heater/air conditioner fan the auto head lights go off. Side lights remain on though. Can you help me?
Hi again Ray, Now I suspect that your vehicle's (BDM)Body Control Module (aka computer) is getting some bad information or has an internal problem. It is good that the problem is present and can be created on command. The tough part is that it can be difficult to diagnose without a scan tool to talk to the computer. I am pretty sure that your vehicle's Body Control Module (BCM) just happens to have the same ground as the fan for the heater and A/C. If the ground is not of good quality it is possible that when the fan is turned on the BCM is getting lost. Computer circuits have to be sound and free of undesigned resistance. The BCM is an electrical whimp. The heater A/C fan is the tough guy. If the ground for the BCM is not the greatest and then you add the high electrical demand of the heater fan, guess who will lose? The BCM will be unable to operate correctly. There is just no telling what unexplainable operations will occur from the BCM. I would suggest having your technician chase down ground #G200. A clean and tight connection may get the BCM back on line.
Pontiac Grand AM - ABS light and Traction light on
Pontiac Grand AM
The ABS light and Traction light in my '99 Pontiac Grand AM with a 2.4 L engine, will not extinguish even after I have changed my pads and rotors. Any suggestions on how to get it to turn off or what to check as to what might be the problem?
Hi Jeff, There is a funny thing about Anti-lock Braking Systems that many people do not realize. The system doesn't know any thing about brakes. That's right, the ABS system doesn't know anything about brake pads, shoes, calipers, rotors, brake drums, etc. In fact, I could remove your brake pads, brake caliper, even brake rotors and drums on some vehicles block the brake line so the fluid doesn't spill all out and your vehicle's ABS system wouldn't even know they were missing.
Computers assume, and take for granted that the core components of the braking system are in good working order.
If you have an ABS light on the first item that should be checked is the brake fluid level. Many ABS systems do tie a fluid level sensor warning light in the ABS warning light. But let's not assume and be sure the brake fluid is at the correct level. You now know that you have good brakes and that the ABS system doesn't know the difference.
The next step would be to have a code check performed on the ABS computer. With the warning light being on there will be a code. That code will direct you in which part of the ABS system needs diagnosis. It is also likely that your traction control warning light will go out once the ABS problem is corrected. The 2 systems rely on some of the same sensors to operate correctly.
Pontiac Bonneville - Noises when passing through water
Pontiac Bonneville
I have a 92 Pontiac Bonneville. When driving in rainy weather, if I run through any water, the vehicle begins to make a terrible noise. You can feel it vibrate under your feet. I thought this was the brake pads somehow vibrating because they got wet, however the noise does not stop or change when the brakes are applied. The pitch (if you will) will change when you place the transmission in neutral and rev the engine. The car continues to run just fine, and eventually the noise disappears. I have thought that water may be splashing up between the converter and the heat shield and is percolating, but that would not change with engine speed. I am at a loss. Any ideas Doc?
Jeremy, the forward exhaust on many vehicles is a dual walled pipe, one pipe inside another. This pipe runs pretty hot and the sudden cooling by water will cause the outer pipe to shrink more rapidly than the inner piper. Yup, that would make for some strange noises, I have run into this problem many times and all the noises you have described fit the scenario and diagnosisp perfectly every time.