I recently purchased a E36 316i 97/P. 2 weeks now and i am having some
problems with either the exhaust or engine. Basically the engine is
blowy, and the rev counter is below 1 at rest. IT feels as though the
engine is about to shut down, and has done once or twice.

Kwik-fit originally thought it was an exhaust problem; the catalytic
converter, which my personal mechanic sort of agreed with. But AA said my
engine needs tuning? I took my car to a BMW specialist, who said it is
neither it's some sort of engine valve which controls air pressure?
Upon discussing this with my mechanic he said this is rubbish, and its not
a valve? What should I do? Any ideas anyone?

Any one know any good BMW mechanincs in West London?