Can Valve Seals Cause Smoke?

It's common for some exhaust smoke to be present when you first start your vehicle, but if it begins to last longer than normal, your valve seal may be deteriorating. In addition, if you have a bad valve seal, the excessive smoke will tend to come in waves as an indicator of oil burning.

Can bad valve seals cause white smoke?

You will notice the most common sign of cracked or worn valve stem seals just after starting a cold engine. ... Once you start the engine, the residual oil gets sucked through the bad valve seal and into the combustion chamber. As such, the tailpipe will emit a bluish white smoke.

How do I know if my valve stem seals are leaking?

One sure-fire way to tell if you have a faulty valve seal, is to perform a cold engine test. Let your vehicle sit over night. The top of the head, will have some oil left over from the last time you drove. The oil will, slowly seep past the valve seal.