Strange AW-4 Shifting Problem

I've been wrestling with this problem for a while now and I'm totally stumped. My transmission started acting up several months ago. When it was cold, the car refused to change out of 1st gear. It would shift to the next gear if and only if I let off the accelerator above a certain RPM. The problem would go away if I drove for a while, but it always came back as the car cooled down.

I bought a junkyard TCM and swapped it in, but that didn't help. I bought an Autozone TPS (I know, I know) and the problem disappeared for several months. The problem came back and I figured it was just because of the crappy "made-in china" autozone TPS. I got a replacement OEM TPS and put it on. The car shifted normally for a single drive and now it's back to not wanting to shift out of 1st.

Things I've done:
Unhooked my TCM and cycled through my gears (fine)
Replaced the TPS (twice, autozone and OEM)
Poor man's Transmission flush (drain, fill, repeat with Dexron.)
Adjusted my kickdown cable

So now that I've narrowed it down to not being the TPS (or I'm the least lucky Jeep owner in the world) does anyone have suggestions on where to go next?

If you have been able to isolate the issue and temporarily fix it, I would suspect the TPS harness or the wiring associated with the harness is damaged. I would start by using some electronic contact cleaner inside the contact points of the harness, and checking the wires for kinks or breaks. Hope this helps.

Note from DJ to karmafox
You forgot the most important information in your opening post.
See Sticky: WANT YOUR QUESTIONS ANSWERED QUICKLEY!?
http://www.naxja.org/forum/showthread.php?t=1018147

Not sure of the year, but here's the information super-highway between the trans/sensors/actuators. Go to post 10.

http://www.cherokeeforum.com/f51/cruiser54s-mostly-renix-tips-153657/

Thanks guys. I got another TPS today and some electronics cleaner. I cleaned the contacts on the large black and gray connectors that relay information from the TPS to the ECU. I also cleaned the TPS connector and the other connector on the same braid.

I replaced the TPS.

Still having the same problem. I am going to clean the contacts on the ECU and TCU connectors tomorrow and if I'm still having problems, thinking about ordering a transmission filter and some new solenoids.

Good plan. There ARE tests for the solenoids, ya know. And pulling the pan and changing the SCREEN are really not necessary. Fluid changes should be fine.

I traced my kickdown cable down to my tranny, but I don't have a linkage assembly on my transmission.

I have an early 96 Cherokee Sport, 4.0L. Does the kickdown cable on my model connect to a cam inside the transmission housing?

It's not a kickdown cable. It's a throttle valve AKA TV cable. Increases trans line pressure according to how far the throttle is opened.