richgeo

Three weeks ago got in the car, started it and it immediately began to vibrate with high revs and white smoke pouring out and would not stop. Turned it off and restarted it with same results. Then I drove it around the block and it finnally stopped. This has not occurred since. Took it to dealer and they could find anything wrong, since not any of the warning lights came on during this occurance. It is a 2008 LS with just 38,000 miles on it. Any ideas what could have caused it?
Thanks

SBlexus

Was the car sitting for a period of time, or was it siting over night?

jmcraney

Sounds like one of the cylinders was getting water into it - an indication of a cracked head or blown head gasket, a condition that will return and get worse.

CJITTY

Wow..that is crazy!! Keep us posted

richgeo

JM craney, what would cause a cracked head/gasket leak on a car with just 38K? Maybe someone to do with the valve springs callback??

richgeo

SB, just sitting overnight.

jmcraney

Well, I think that a head gasket or cracked head is an extremely wild guess, however he didn't mention any oil residue or odor from the smoke. What else makes odorless white smoke and no reside? It was a sort of a "straw-man" answer to stimulate some knowledgable person to help.

You need to keep in mind that certain atmospheric conditions make the exhaust more visible when the engine is cold and that effect goes away as the car warms up. And sometimes starting a car for a short time when it is cold and then turning it off will leave it sort of flooded and cause it to run rough the next time it is started. Since there was no forensic evidence such as residue or OBD log perhaps it was a convergence of coincidences.

richgeo

JM, there was a somewhat foul order from the smoke, but I can't remember what to compare it to.

jmcraney

When we start the car cold, for a short time, and turn it off it leaves it flooded because the fuel/air mixture must be very rich and the RPMs must be high to keep it from stalling. That leaves some raw gasoline in the cylinders that will foul the spark plugs, causing the engine to run rough and the exhaust to smell of raw gasoline when the engine is started later.

I did this trick a few days ago by leaving my car sitting in the driveway for a day, and then moving it into the garage the next day, about 15 feet. Then the following day I cranked up and it ran very tough until I had driven the equivalent of two or three blocks.

These are normal events when gasoline is used for fuel and although they are disconcerting they are not usually an indication of a problem.