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Audi 100s 1993. White smoke when starting

Hello all, I have a 1993 Audi 100s 2.8L V6
It needs new spark plug wires for sure. However recently when I start it up it has been blowing white smoke out the tail pipe and runs really rough. However once I run her for a while smoke goes away even when heavily accelerating. Also when It runs rough I can smell raw gas. Does anyone know whats going on to my car?

White smoke with the smell of gas indicates there’s unburned gas coming out the exhaust.

You need to figure out why the engine is flooded when it’s first started.

It could be something like a defective fuel pressure regulator.


White smoke that goes away and bad plug wires with raw gas smell, I would guess bad head gasket and misfiring.

Do you have to add any coolant? How many miles per quart of oil?

Are you doing the work yourself? If you are, remove the sparkplugs and compare them to the chart in the attached link. Post back with the results.

You clearly have at least one cylinder that isn’t firing when cold, blowing unburned gas out with the exhaust gasses from the other cylinders and causing rough operation and the gas smell. The cause could be as simple as a bad plug wire (you already know these need changing), a bad plug (I assume these need changing), a bad distributor component (is this '93 a distributor based system?) or something a bit more sinister. The good news is that these types of problems are generally from long-overdue maintenance; like a long-overdue tune up.

So I installed the new wires and plugs and am still having the same problem. When I first start it up and begin driving the RPMs drop even though I have my foot down on the gas pedal. Still getting white/gray smoke out the tail pipe during this time but seems to be less in quantity.

Is your check engine light on? Leaky injectors… it could be a bunch of things. If you have a head gasket leak it will not get better. You need to get the codes read and have a leak down test done. Leak down test will prove or disprove the head gasket leak.

Check Engine light is not on. I will take it in and have them run the codes. Thanks.

Valve stem seals??