Hey guys,
I noticed that after I drive my car hard for a short time (floor it) and then park it for a few hours I get some whitish grey smoke at startup for a few seconds and then it stops. It also kind of smells like burnt rubber. If I don't get on it, no smoke just a little smell. My mechanic says that it could be unburned fuel in the exhaust system burning off when it heats up but it comes out pretty quickly after I start it up and only for a few seconds.
Any thoughts?
Thanks!

 

Coolant getting into the combstion chamber somewhere. Good luck finding out where though. It could be through the head gasket, or possibly from the intercooling system.

 

I agree with ohsigmachi, check your anti-freeze level. I had a similiar problem with our '97 GTP, I took it to the dealer, they scanned it and the scanner told them it was the front side head gasket. Well worth the dealer diagnostic fee. Over to the zone picked up gaskets and then to the bevie store for some cold 1's and corrected the problem.

 

I agree with the leaking head gasket theory. Your case sounds pretty classic to me....

 

No. Valve stem seals will cause blue smoke from burning oil. Not white.

Blue Smoke = Oil
White Smoke = water or coolant
Black/gray Smoke = fuel

I would check what has been recomended but I don't think you have a problem. Just left over stuff from getting on it!!

Remember that under full throttle or WOT conditions the computer is not looking at the O2 sensors and adjusting the amount of fuel. The amount of fuel is almost always set rich under these conditions to protect the engine. Especially with a super charged engine any slight lean condition while under boost will roast a piston very fast. You just can't risk it!!
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I think that if it is coolant that it is from the inter cooler because it comes from both pipes equally and the coolant level barely goes down at all even with time. Also because it only happens when I get on it I'm probably forcing an otherwise very minor leak to get worse under pressure. The supercharger was replaced once by a jag dealer that took 6 times to (TRY) to fix an expansion tank leak and I finally gave up on them. I'll bet they screwed something up in the install. There were 2 times a couple of years ago where thick white smoke came out of both pipes but just for a few seconds. Now it is pretty faint and only after getting on it and parking it for a few hours. Like it keeps dripping for awhile after I shut her down. The longer I'm on it the more smoke that I get but still not bad. And as I said the coolant level never goes below the MIN. mark.
Thanks for all of your input.

 

I wouldn't sweat it. Same thing on both my first 2003 STR and my Lexus GS400. If I started the car for a short time period; i.e. moved it in and out of the garage and shut it down - then the next start-up I would have smoke. Always figured it was the unburned "rich" fuel mixture that occurs upon start-up.

I too figured it was either coolant or oil - neither proved to be correct.

Certainly worth a leak down (oil/compression) check and/or constant monitoring of the coolant level but I wouldn't take a withdrawal out of your bank account just yet for a repair.

Good luck,
Eric

 

Thanks everybody for your input. I will keep an eye on the situation.