White smoke is a symptom of a blown head gasket.
Head gasket or cracked head
No. A bad head gasket would cause water to come out the tailpipe. You will see white smoke. Leaky rings would cause oil to come out the tailpipe. You will see blue smoke.
I had that happen to me with a V8 I was driving once. Turned out that I had a crook head gasket and oil was being sucked into cylinder head burnt and then out the exhaust. That is white smoke, You it might also be worn oil rings, (white smoke) Or if you are running on a rich fuel mixture you may be blowing black smoke.
There could be many problems related to smelling gas and seeing white smoke from your tailpipe. Some suggestions would be the head gasket. If the smoke has a blue tint to it, it may be oil related. If your car has a turbo, it may be the turbo needing to be replaced. To be sure, you can have a mechanic do a diagnostic on it.
you put too much oil in, it is burning the oil.
engine coolant getting into an engine cylinder from a bad head gasket , cracked or warped head
Yes. It also depending on what kind of stop leak and how much is used.
I feel these are unrelated but you can investigate a leak in the hoses leading to the heater core as they maybe leaking onto the exhaust pipe, that would produce white smoke, but not from within the tailpipe exhaust. Water and oil leaks will produce white smoke the smell will help you determine which it is.
blow by through the turbo ,my truck did the same thing had to get the turbo rebuilt
Take it to a mechanic right away. The white smoke is from fluid mixing with the oil in the engine. Its probably the head gasket.
If it is blowing white smoke out of the exhaust tailpipe when the engine is at operating temperature, engine coolant is getting into an engine cylinder from a bad head gasket or some other problem