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Thick smoke from tailpipe

I drive a 1993 Cadillac Deville.Yesterday i started the engine with no problems,but as it sat idling,i noticed allot of white smoke with a light grey/bluish tint coming from the tail pipe.I put a white paper towel up to the tail pipe to see if anything else was also coming out.The paper towel some light,pale green wet spots,and a smell of oil/fuel.When i checked the oil level it indicated the engine needed a quart of oil which i put in.At that time i left the car alone.

When i went out to the car to go to work i noticed a puddle of oil (4-5 inch diameter) under the engine.When i started the engine some smoke originally came out but seemed to thin to normal.As i dove to work (3/4 mile drive) the car seemed lacking of power and again some very thick white smoke from the tail pipe each time i accelerated.There was no sign of water leaks anywhere under the car.Again idling in park the smoke remained constantly thick white.Also while idling in park i noticed the sound of the engine was not the normal steady sound,it was now more of a sputtering sound.

I checked the oil fill cap and didn’t find any milky or greenish film nor any water.The radiator is full as is the antifreeze reservoir.On the way home from work the service engine light came on for the first time.No other indicator lights came on (they do all come on when ignition is initially turned on for bulb test),and no codes show up on the diagnostic system. Any ideas,suggestions,trouble shooting tips?

Congratulations on being prudent. You may have just saved your engine by doing so.

I’d get this towed to your shop and checked out. We’ve had numerous posts here about bad GM intake manifold gaskets leaking and causing these sort of problems. I’m not personally familiar with the details of the failure mode, not being a GM guy, but know that if you get coolant mixing with your oil you could sustain serious bearing damage.

Multiple problems.
“Check engine” light with rough idle but no code.
Oil puddle under car (and the size is significant).I can’t make a conclusion about the color of exaust,your description runs the whole range.
No loss of coolant,oil shows no contamination.
Repeat process to retrive code,have cooling sysyem pressure tested,make inspection to locate oil leak.
You could pull plugs and check if they indicate coolant is entering combustion chamber.

Check and see if the transmission has a vacuum modulator. If it does, it might be that the diaphram in the vacuum modulator has ruptured, and now the engine is pulling tranny fluid into it via the vacuum hose and burning it.


A head gasket or intake manifold gasket seems to have blown. Either way, water is getting into the combustion chamber. One of your spark plugs should look really different than the others.

I’m with pleasedodgevan on this one. The spots of green fluid spitting out the tailpipe make it imperative that the engine be looked at for the possibility of a breech in the manifold gasket or headgasket.

Again, I commend the OP for his diligence and also for his paper towel protocol.