1. Idle with black smoke.
2. Engine jerk when idling.
3. spark plug goes black and after replacement its ok for a while but later will be like running on 3 cyl.
4. Changed plug ...
wazzup yall 7sifu...normaly if yall change da back box exhaust wut happend with da catalytic converter...did yall change to new one or just take it off??ist ok to take it off or just leave it there?..coz i read one...