My throttle was sticking so I opened it up by turning the screw about a 1/4 turn or so and now the stang shuts off when I put it in reverse from park...outside of that it runs while. This is only after the car has been driven for a while and is more than warmed up. I'll put it in reverse and the idle will drop really low and then surge up or idle really low and then shut off. Can I get a new TPS to solve the problem. I know I can reset or alter the TPS but don't have the tools or time to do so. Any help would be great. Thanks.