I washed under the hood of my 88 cherokee and went to drive and the trans wont shift out of first gear. When i unplug the TCU i can shift the trans through all gears just fine so i think it is mechanically fine. The engine runs fine so im assuming the Throttle position sensor is ok and the speedo works so that sensor seems fine too. Any hints? Is it possible to rent a DRB II scan tool at an auto parts store?

Thanks for yor help

 

I think the shift is done by a cable from the throttle linkage into the transmission.

Has the cable come off at the Transmission end?

 

you prob got the TPS wet........get a voltmeter and see what it is doing.........

 

Exact same problem on my 91 it was theTPS

 

Well after letting the jeep sit all week while i was back at school whatever was causing me the problem last weekend has dried up. I guess my sensors or connectors got water in them somewhere shorted out and confused the tranny computer. Shifts perfect now. I have a feeling i will see this problem again however

 

next time you was the motor cover the throttle body and sensors