I helped my dad buy an off road h-pipe and two chamber flows for christmas. Now that they are installed he is complaining about the car not having as much power as before and when you get on it it blows black smoke form the pipes. It is also smelling very rich. I mean you can smell it from inside the car. The day after he had them installed a deer ran out in front of him and he went backwards off of a 15 foot of so ditch. The car is fixed now and they said nothing was hurt except for the body with scratches and such. I am not sure if that is the case or not. Does anyone have any clue what could be causing this problem. Oh yeah he also has a Diablo chip in it that was burnt and put in before the exhaust was put on . Thanx for any help.