aw4 problems

just got an 89 xj with an 4.0/aw4/231/dana 44 for $480. It made the 1.5hr drive home fine, but there is an issue with the tranny....on accleeration, underload, and during decceleration, tranny shifts fine. While driveing down the road though, around 30mph and on the tranny seems very jumpy like the accererator padal is really touchy. The speed/rpms will jump and there is a clunking type noise that doesnt sound like it is caused by mechanical problem. Anyone have any ideas? Jeep has 250000 miles...

Kevin

Okay, sounds like you've got a few things going on here...

1: Shifting. I would be willing to bet that is a faulty and/or out of adjustment throttle position sensor. Cherokees get their downshift signal from this sensor as opposed to a kickdown cable or rod (like older vehicles). Adjust the TPS; if you cannot adjust it to spec then buy a new one and adjust that into spec. The procedure is here: http://xj.sequoiasite.com/tech/autotranstps.pdf

2: Clunking. By the description of the problem and the age of the vehicle I'd be willing to bet that the motor mounts and possibly transmission mount are shot. Personally I wouldn't go with OEM style motor mounts, get Rawbrown or MORE mounts and they'll last a lot longer. If money or time (parts availability) are a concern OEM units are fine, you just won't get long life out of them (my replacement OEM style mounts lasted me about 1.5 years of daily driving plus trail duty).

3: Clunking part 2. I would also give a good hard look at the U-Joints in the driveshaft(s) and front axle (if so equipped).
Sequoia

followed the link is the connector marked A B C D? just got home and need to do this? or do you have a diagram of which is which?? Thanks, John

my 87 has the markings a b c d . You might have to clean the conector a bit to see them.

Look real close the connector should be marked. Good price, hows the body?

the wiring from the tps actually splits and has 2 connectors I"ll check in the am with some light, thanks

it's the connector that is plugged into the TPS. You need to backprobe it.

got it thanks all