ive searched and searched and searched, i cant figure this one out! i have a 95 318ti and i love this car, but it idles rough, and sometimes dies. i did the stomp test and got 1226 knock sensor #2 so i changed all my spark plugs, changed oil, pre cat o2 sensor, and checked for vacuum leaks, it didnt help. so i cleaned my icv, didnt help. im pretty sure my mixture is lean so i bought a new MAF sensor and im currently waiting on that. but something weird is when i take my oil cap off it doesnt have suction, it has the reverse it blows out not sucks in. can any body help me figure this out?