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Bad Smoke Help Please

1456 Views 15 Replies 6 Participants Last post by  CadillacSTS42005
Ok so my mom has a 96 Sedan Deville with about 110,000 on the clock. For awhile when you floor it and i mean floor it at high speeds the SERVICE EMISSIONS SYSTEM light comes on. Also if you leave her car ideling for about 2 minutes and hop into it and rev it (even if it has already been run for ahile before hand and the engine is all warmed up) The thing BELLOWS white smoke and i mean bellows it looks like she lit up the tires and is smoking them off. Could these problems be realated? I can get the SES light to go off if i put the car in park rev it a little to clear it out and then shut the car off open the door, close it and then restart it. I checked the codes and got some EGR valve code. Before i spend 150 bucks on an EGR id like your input.
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What is the egr code? I am thinking it is possibly the one about egr pintle valve out of range?

Before you go out and buy a new one you can clean the one you have. Remove it from the vehicle and examine it. You will notice that the valve stem gets carbon on it. What you need to do is clean this. You can use carb cleaner. Follow this one not let the carb cleaner get into the windings inside the valve. Hold the egr valve right side up the whole time. When you spray the carb cleaner, don't shoot it hard up in the valve. I used a small babies toothbrush to help me clean it.
I would rather just buy a new EGR and install it rather than clean it.

If its bellowing white smoke I would really drain the cooling system and replenish with dexcool, that thing may have a blown head gasket.
That is fine it you want to spend the money. Cleaning it works just as well. You clean carbon and gunk from your throttle body instead of buying a new one. Same difference, not hard to do.

How is a drain and refill going to solve the problem? Do the small checks for leeaking head gasket if you are going to go that route. Does the exhaust have a smell?
I think you have two seperate problems. The EGR is obviously one because it set a DTC but, A bad EGR should not cause white smoke. Like Eldyfig said, what does the smoke smell like, fuel or a sweet coolant smell?
smells wet not like fuel idk not like coolant tho i dont think. and yes egr pintle valve out of range is wat it ment.
I'm not sure what you mean by "smells wet". Thick white smoke is typically coolant or an extremely rich fuel condition. In either case the smell should give it away. If it is fuel, look for a bad FPR or stuck open injector. If it is coolant, it is likely head gaskets.
Just clean the EGR valve. A new valve is not required at all. Remove the valve and clean the pintle valve and the pintle valve shaft up inside the passage in the cast base of the valve. The deposits on the shaft are usually what cause the shaft to hang in the seal and cause the code. Be carefull to NOT let any solvent run down the shaft into the can of the EGR valve. If any solvent runs into the can it will eat the insulation off the wire windings inside the can and ruin the valve. Hold the valve right side up when cleaning with solvent so nothing runs down the shaft.

The white smoke may be a stuck open injector or a failed fuel pressure regulator. I would check the FPR first. Pull the vacuum line off the FPR while the engine is idling and see if there is any fuel in the line or coming from the vacuum nipple on the FPR. Apply a vacuum to the FPR vacuum nipple and see if any fuel comes out. None should.

If the white smoke is coolant it should be pretty obvious that the coolant level in the cooling system is going down. If there is no coolant loss then I wouldn't suspect it is coolant intrusion.
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no not really a coolant loss except recently cuz the waterpump went (had it replaced) havent noticed a loss since nor has the temp gone above 220 max
CadillacETC1997 said:
bump HELP!!!
Have you attempted any of the ideas listed thus far?
I cleaned the EGR valve and the message hasnt appeared since but it only came on rarely in the 1st place. Its the smoke that im most worried about. I pulled the coolant res cap while the car was running and no bubbles so im hoping that means no head gasket leakage.
Get down by the tail pipe and get a good wiff of that smoke. It should be a dead give away as to wether it is fuel or coolant. If your coolant is not going down, I'd suspect fuel.
thats just it i really dont notice any smell it just smells like "normal" exhaust does (smells the same way from my ETC and my dads 98 STS) its just theirs a crap load more pouring out.
You cleaned the egr, good job. Wasn't hard, was it? I would go with one step at a time. Good coolant level, no bubbles...good. Checking the FPR is not hard to do either. Do as recommended for that and then post back.

Don't let the paranoia about headgaskets get you. Granted, there are headgasket problems, alot of cars have them. I personally don't think that is where you are headed from what has been posted so far.
alright thanks guys ill check that out 2marrow while her car is in the shop for a new Alt (yea yet another problem with her car)
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