mattmudby

i swapped a running 1988 4.0 out of a manuel jeep into a jeep with an auto..the guy i baught the auto jeep from said it shifted fine and the tranny was in great shape. it just needed a moter. so i did the swap and got everything running and it wont upshift. i unplugged the tcu and it shifts. but with it plugged in it wont..my question is could it be the tps instead of the tcu?? is the tps diffrent from a auto engine or not. and were is the tps located? plz i need help lol

XJ Stryker

TPS is located on the front of the Throttle body.

It is Adjustable on Renix engines (87-90) I am not sure if there is a difference between auto and manual as I have never heard of it but then again I don't pay much attention to Manuals.

Here is a great link to bookmark for renix engine owners.

http://www.lunghd.com/Tech_Articles/...iagnostics.htm

FourWinds

I say it's probably your tcu. Even with a bad tps (on the tranny side), my 88 shifted but not at very good shift points. After replacing my tps it shifted more like it should've. A while after after replacing my tps, the tranny stopped shifting at all. I unplugged the tcu and it shifts manually, which is a pain.

The tps is different on an auto trans vs manual. The tps on the 88 is located on the front of the throttle body next to the idle air control toward the outside of the vehicle. The auto tps should have two different connectors to ensure you don't cross connect them, one a four holed square and one a three holed inline.

mattmudby

i dont think it needs to be adjusted becuz it ran fine when i tood it out of the other jeep. i read somewhere that a manuel has one potentimetor and a auto has 2 or more? is this right..will a manel tps work with a auto trans?

mattmudby

would the diff tps cause it not to shift corectly

FourWinds

The manual has one and the auto has 2. The manual won't really work with the auto because you need the 2nd pot.

FourWinds

I'll try to post a picture of mine.

FourWinds

Okay, here it is... a picture of my '88 AW4 tps. The tps is in the center of the picture and has two different connectors with the wires being colored the same for both: blue, black and white. One connector for your ecu and one for your tcu.

mattmudby

thanks ill go try and change it tomarow