So I have an 86' sport coupe with a four speed auto and its having a bit of a problem. When I take it on the highway its fine at first, but when I go to pass someone it drops into 3'rd to get the passing power, but after I reduce my speed it stays in third. Then when I get off the highway it drops to first and refuses to shift out of it until I restart the car at which point everything returns to normal. Any ideas?

 

I'd start with www.thirdgen.org/detent and check the electrical connector to the tranny as well. The electrical connector only supplies control of the lockup torque converter, so has nothing to do with 1-4 gear changes, that's all controlled by the detent cable.

 

this looks helpfull but I'm having trouble finding my TV dent assembly

 

two cables connected to the carb, one is throttle, one is detent.