oil leak!

[mark wolfson]

Say, brought my '85k to local Audi Dealer to have cam seal replaced. Yep, after being told old oil wiped away and no  more oil leak (from front of engine, down low) still leaking. I have had the car for over 3 years, and still cannot get oil to stop leaking. Is there some sort of magic to get oil leak stopped? Oil temp switch seems to have been replaced at least twice. Is there also a problem with the threading into the female end of the switch holder? Aside from this (getting sidetracked), what can I do? What am I missing here?