tmhalbert

I've got a 1996 Cherokee Country with the 4.0 242 I6 Engine, NP231 Transfer Case, and AW4 Auto Transmission. The jeep has 218K miles and I bought her totaled about 2.5 years ago. I put $300 worth of JY parts on front-end, got her restored salvage, and have been driving daily ever since. Maintenance on the part of the previous owner doesn't look to have been very consistent ... anyways, here's my newest problem...

I've been experiencing some intermittent, but increasing Torque Converter lockup issues now for about 6-8 months. Sometimes (rare and extremely intermittent) this increases to being stuck in 3rd gear and then is always followed by extreme slipage when starting from a complete stop.

When it's just TC Lockup issues, coming to a complete stop for just a second will resume normal operations. On the rare occasion when the transmission kicks down to third and won't go back into OD, I get off the highway and baby the Jeep to a safe place. This is when I get really bad slipage from a complete stop. Once I'm somewhere safe I shut her down for about 3-5 minutes then start her back up and she drives perfect.

Like I said before, this problem has been occurring for about 6 to 8 months; and before you scold me for driving her into the ground or not searching this site for solutions, I have been actively working on a resolution:

The first thing I did was replace the TPS. The first TPS I got was a Duralast from AutoZone; no luck. I swapped it for another Duralast and again no luck. I then tried a BWD TPS from O'Reilly; better but still having the problem.

Next I just said **** it and went "all-in" and replaced the transmission. When I first picked her up I could feel a huge difference from a complete stop and thought I solved the problem ... until I got on the highway. I had no OD at all; back to the shop. After replacing the torque converter (they actually reused my old one.. idiots) OD was back but the problem was still there. After 2 more transmission/torque converter swaps the problem is STILL occurring. However, this latest transmission feels stronger than ever when it does work!

Yesterday I tried adjusting the TV, or kickdown cable. I pressed the button in, slid the casing all the way in, released the button, opened up the throttle to WOT, heard the clicks and took her for a drive. I thought I finally fixed her until my drive to work this morning. She only slipped out of lockup once, and just for a second. So the problem seems to have improved, but it just won't go away!!

Now I need your help. Would it be worth replacing the TV cable? Or how about my Catalytic Converter? Or even the computer? All of the above? Then which one should I do first? Maybe there is something I haven't even thought of? I'm out of ideas and worried that it could be an electrical problem; not my strength!



Thank you for taking the time to read this and I greatly appreciate any help and all responses!

Tread Lightly ...

salad

Ever look at the brake pedal switch? The TCU will unlock the torque converter if it thinks you're on that pedal.

tmhalbert

I did not...

Is there a write up on testing the switch, or should I just replace it and see what happens? If so, do you recommend brands to avoid, like Duralast...?

EDIT:

I'm at work right now, so I'm going to have to look at this later. However, I've been on Google and through this forum for the last hour looking into this. If my cruise control doesn't disengage, and I don't think my brake lights come on when the Torque Converter unlocks, could this still be the problem?

On my way home I'll try tapping the brake to see if my RPMs jump, and if/(when) it kicks out of lockup I'll lift up on the pedal to see if it locks back up.

Also, would the transmission solenoids be replaced in a full rebuild? I would think so, but could this actually be the problem after 3 new transmissions??