My jetta has had an interesting few months. It started in December with a connector hose for the radiator rotting and spraying coolant allover the engine and overheating due to that. That was fixed. Then it was having a horrible "misfire" The computer said it was the coil pack. That was replaced and two coil wires that were showing misfiring were replaced. That didn't fix the "misfiring" (car bucking and running rough). The computer scan said it may be a computer issue and a replacement one(not necessarily factory) was installed. Now the car stalls in reverse, but only when it is warmed up (driven for an hour or longer) It's been looke at by my mechaninc and a reputable vw mechanic in the area and we're all stumped. Any ideas?