Recently my 89 1t has this problem, but only when put trans selector in D. The pedal acts stuck, can't accelerate, if extreme pressure is applied by me the cable pops out of the pedal arm, but only in the fwd not reverse. Has anyone experienced this, I am trying to find where to look before going under the truck. This happens 99% of the time, I checked all linkage at or on pump and all seems well, is there something down on the trans that I should look for? Tom L