Underneath the air cleaner and turbo are both oil return to sump and oil mist venting pipes that have various O-Rings and grommets, so on and so forth .

Once I replaced all of that on my Coupe the oil usage dropped to almost nil even though the engine blows a bit of blue (oil) smoke .

I'd begin there, the lower oil return pipe is a very common culprit .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better