I have a 1992 200TE wagon. It is running rough, and had intermittent throttle delay problems. After visiting 4 mechanics i eventually went to an exhaust shop this morning and they tell me that there is a rattle from both my catalytic converter and sure enough it has had a bash. There is also a rattle from the centre box. I have been quoted EUR740 to replae them both with no guarantee that it will fix the acceleration, but that they do need to be replaced. I want to sell this car on and buy a newer one so putting any money into it now does not appeal. Can i source a second hand exhaust and cat? Is it possible to fix a second hand exhaust or is it a big No NO?