I just replace my valve stem seal myself for more than a month now due to white smoke, while i was in there i also did timing chain replacement. For more than a month i'm glad that it resolve the issue no white smoke coming out and drive fine until yesterday when i did another change oil and i notice the white smoke came back. It only showed up when the car is idle for more than 15 minutes but its not worse as the last time i haven"t replace the valve stem seal. All parts i replace is oem one so i didn"t know why the white smoke cameback after a month. Any input what went wrong?

 

White smoke usually means burning coolant
Blueish smoke usually means burning oil
Blackish smoke usually means too much fuel

I’m going to assume it’s actually blueish smoke. You can double check if it actually smells like burning oil.

You say it only happens when the car idle for more than 15 minutes? You mean the engine is idling for about 15 minutes, that’s when the smoke starts? Or is it only if the car sitting without running for more than 15 minutes? If it’s the first situation, I would suspect an issue with the PCV system. If the repairs are indicative of higher mileage, chances are good the cam cover needs to be replaced. (PCV valve is integral to the cam cover) You might be able to get away with adding an oil catch can, but it might be a good investment to replace the cover.

 

Thanks for the advise, yeah it only occur when the car is park and idle for about 15 mins and only when i start to press the gas the thick smoke started to accumulate. I haven"t replace the valve cover but i will buy a new oem one i am the second owner maybe they didn't replace it yet and its about 50k in the odometer. I also check the turbo oil feed line for leaks but its fine not leaking any oil.