Hey guys my car is an 02 ba xr6 turbo ( 4spd auto) with ~158k on the clock only mod is centre muffler removed. It seems to be missing or something and the exhaust is popping and kind of shuddering under wot, we checked the plugs and coils and they appear to be in good contidion, also in 2nd gear it wont rev past 2500. Any help would be great.