I was stupid enough to buy another trans with 74K low miles and installed. well newly installed trans does same as old one did. 1-2-3-then start to lockup and then nuetral. Rev up and down, nothing. the only thing now is pull down into 3rd to drive. In third it drives normal with out lockup, shifts correctly I mean. just no lock up 4th.
What is up.
Nuetral/manual/ switchs are still with trans that came with, so how could it be the switch with two differant ones installed.

Please help, I am not money rich to take to a GM Dealer.

Throttle position sensor "correct" adjustment coupled with rpm input equals correct engine load as determined by tranny computer.

New TPI sensor two weeks ago, no differance. there is no adjustment on the TPI sensor, how do I adjust that. Also where is the speed sensor.
Solo

I swaped the two sensors, in and out, still same situation. What should I try next.
Solo