I have a 1999 A4 with 116000 miles and I bought it 3 weeks ago knowing that it smoked. I thought it might of been the rings but I did a compression test, and it has good compression in all cylinders. Then I checked into the valve seals and I asked a Mechanic and he said they rarely go bad. I rebuilt the turbo because there was alot of play in the shaft, and I thought oil was leaking into the turbo. I just drove it and it smokes, then stops for a little, and then starts again. Any help would be appreciated. Thanks.

 

what were the actual numbers from the compression test on each cylinder? do a leakdown test to check if the valves are leaking, valve guides and seals going bad does happen. if the oil leak isnt coming from the valves or head gasket then it would have to be coming from the turbo seals. are your spark plugs fouled with oil deposits? is any one plug more fouled then the others?

 

What are your thoughts on the rings being stuck? When I did the compression test it was before I rebuilt the turbo and there was an excessive amount of oil in the cylinder due to a bad turbo, helping seal the cylinder, which would give a higher compression reading.

 

Retest the compression both dry and wet and see...

Question: When does it smoke? During cruise, acceleration?

Could be a bad rear crank seal if it smokes alot under acceleration.

 

Are you sure the turbo is not leaking oil?

 

After you rebuilt the turbo, did you remove and clean the boost hoses and intercooler? Are you sure it just isn't residual oil?

 

I cleaned all the hoses and intercooler in my parts cleaner and blew them out with a air hose. I drove the car for maybe 10 minutes and it started smoking almost exactly the same as it did before I rebuilt the turbo. I also noticed when I remove the oil cap it seems like theres alot of blowby. When I set the cap on loosely on it will hop around. Im not sure if thats normal?

 

PCV system working?

 

When I replaced my bad turbo with a blown oil seal, it took about 30 min of driving before all of the smoke disappeared. Perhaps you just need to drive it longer? Also, monitor your fluids (coolant/oil). If it's not a bad turbo, then a lack of oil can make your seal go bad again and cause your turbo to go bad (as in my case).

 

Can you post the numbers from your compression test?

Have you replaced the oil filter recently?

Is the PVC system dumping oil into the intake?