Help!!! Right i have a 2002 3 series 316ci 4 door it started lacking accelaration like a real flat spot in revs but fine afte rlike 4000rpm, sounded like there was no air fikter on it so took it to a garage had the the coil pack plugs air filter and air flow meter changed got it back was running better but still gad a flat spot in revs mechanic said its the cat poured some stuff to clean it he did and no luck an few days later eg today car just wouldnt start turned over but didnt fire up, hes now saying fuel pump and relay and possible injectors are bad??? Any suggestions am i having my pants pulled down?