91XJ, Transmission problems...

[dwebb944t]

Hi, I am new to the list... please bear with me

I have a stock 91 Cherokee with the AW4 transmission, it is shifting wierd, sometimes it will stick in 3rd gear sometimes in 2nd gear. Sometimes it shifts perfectly. I have replaced the TPS and it did not help. Could it be the TCU or NSS? Any ideas?
TIA,
Dan

 

[richdoo]

Here this may help

 

[DaveD in Canada]

Sounds like the infamous bad TPS ground! Try splicing a new ground wire into the TPS harness at the connector, and ground it to the engine or throttle body. This fix has worked for scores of XJ'ers. Make sure you get the right wire, any other wire besides ground will really mess things up.

 

[dwebb944t]

Sounds like the infamous bad TPS ground! Try splicing a new ground wire into the TPS harness at the connector, and ground it to the engine or throttle body. This fix has worked for scores of XJ'ers. Make sure you get the right wire, any other wire besides ground will really mess things up.

Cool, I will try it, does anyone have a description of the pin outs for the TPS, or a cheap manuel to recommend?
Thanks,
Dan

 

[SOOLONG]

There are three wires in to the TPS. The blk/lt blue is the ground supply wire coming from the ECU the orange/black is the TPS in to the ECU and the violet wire is the 8 volt supply from the ECU. Hope this will help.

Joe

 

[SOOLONG]

OOPS! The viloet wire is 5 volt supply not 8 volt.

Joe

 

[dwebb944t]

So, I should take a wire from ground and splice into the blk/lt blue wire? And I should have the harness plugged into the TPS when testing right?
Thanks,
Dan