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White smoke on acceleration

1999 VW Passat with 70,000 miles sends a puff of white smoke from the exhaust pipe while accelerating. Any ideas what the problem is?

Is it a diesel or gasoline? Does it make a difference warmed up vs cold start?

Unfortunately, if it’s doing it all the time, that white stuff is burning coolant which means you’re probably looking at a head gasket.

Agree that coolant must be entering the combustion chambers, and you should fix it right away! On older cars with vacuum modulated automatics, it could be transmission fluid due to a ruptured diaphragm.

Stand behind the car while someone accelerates the car. Does the smoke smell like antifreeze or like fuel (gasoline or diesel)?
If it smells like gasoline, there’s a fuel injection problem.

Gasoline

And just a puff while accelerating, not a constant white smoke

Tom,
Who are you answering, Hellokit or GreasyJack? Is your answer that it’s a gasoline engine, or that the exhaust, upon acceleration, smells like gasoline?
Your answer could be the salvation of mankind…Well, not really!

Gasoline Engine

I don’t know the smell at this point.

Sorry for the confusion,with mankind hanging in the balance!

It could also be vaporized water that accumulated in the exhaust system while driving without accelerations, but you need to smell the exhaust too.