I drive a 2002 Toyota Camry. Most recently I’ve noticed a bluish/white smoke that is discharged from the tailpipe upon starting the vehicle. This situation only occurs in the morning and I cannot see a continual stream of smoke being discharged as I drive or accelerate.
The most common cause of this is leaky valve guides. As the car sits ovenight, oil leaks past the valve guides into the combustion chambers (cylinders) and upon starting this oil burns off and mixed with cold exhaust gas (because the muffler is cold) shows up as blue-white smoke. One way to verify this is to take your foot off the gas pedal at highway speed, and look in the rearview mirror. The engine vacuum created will suck oil past bad valve guides and also cause blue smoke. This works better with a stick shift than with an automatic.
Another possible cause would be some coolant leaking in to the engine because of a bad head gasket. This would also cause the engine to boil over when the car heats up.
In any case your mechanic should perform a leakdown test and further examination to determine the cause.
Most older cars have valve guide problems and most owners just keep driving. Depending on the mileage and general condition of the car, and the severity of the smoke, you may decide to do the same. If the car needs to meet an annual emissionj test, you may have to fix the problem.
Thank you for the detailed explanation. Will keep monitoring the severity of the smoke for the time being. Again, many thanks.
Maybe you will want to be a little more proactive. That oil working through the system can damage the converter and you might end up buying a new converter as well as fixing the problem. The converter can take some oil and yours may not be too much yet, but it is hard to say how much is too much until the converter goes.
I echo Docnick and add that valve guides also have seals . . . little rubber gaskets (kinda like an “O” ring) which harden and crack over age. One of those high mileage oils might soften them up enough to stop the leaking, if that’s what it is. Couldn’t hurt to use this on your next oil change. Rocketman
Sorry . . meant to say valves have valve stem seals, not the guides themselves. Honda sells a kit for my Hoonda which I replaced when it was doing exactly what you describe. Rocketman