Smoking problem: Fixed

[stiubhartach]

Good post in #146. I agree with him and disagree with the follow up posters who claim to be BMW techs. I've known some terrible techs who were just glorified parts changers and didn't understand systems at all. Valve stem seals do fail, but CCV vacuum leaks are more common and far cheaper to fix. Remember as you diagnose ,that residual oil in the manifold and hoses will take a while to clean out.

Don't drive the car with a plugged CCV system. The crank case needs vented to the outside air to allow blowby to escape. The intake manifold hose port can be plugged indefinitely.

I fixed an old Alfa Spider I owned by putting a catch can in the equivalent vent line. I just manually drained it once in a while.

Good hunting!