Well, my friends idea didn't do anything to change the symptoms. It was just a different way to mess with the kickdown cable. I was hoping it would work, but no.

So, after grabbing some dinner with the family, I went and inspected the brake switch a little closer and realized my brain was working in reverse. While I was at work earlier, my mind was telling me I should have a gap between the pedal and the plunger/button, but after smacking myself in the head, I realized I was thinking about it backwards, and when the button is released, is when the switch is engaged.

With the proper mindset, I did notice that the button could be pushed in just a bit more. So when it gets light, I will try adjusting that and see how it goes on the way to work in the morning.

More updates tomorrow.

Also wondering if there are tests I can do with the multimeter. I'll see what I can dig up in the FSM

 

Update: I adjusted the brake switch, but it made no difference to my problem. The FSM I have, gives me a testing procedure with a multimeter, but the switch it diagrams, does not match what is on my jeep. Another oddball '96 piece I guess.

I have a FSM for 95 XJ's, and the switch in that, looks the same as on my '96, but I could not find a testing procedure in that FSM, so not sure what the next step is with the brake switch. I'm sure I can the info somewhere on the web, so I'll keep researching that.

I think my next task is going to be to check the ohms on the solenoids and see if the number three solenoid gives me any indication of a problem.

I'll also have to read up on any possible testing techniques for the TCU. My local junk yard has a tcu for a 96, but I really don't want to throw any money at a "possible" fix.

One other thing I was thinking... The TPS I put on a couple of months ago, in my first attempt to solve this, was an Echlin from NAPA. I haven't seen to many horror stories on the forums about that brand, but figure it might be worth my time to exchange it for another one, just to see if I might have gotten a bad one. It won't cost me anything but a few minutes of my time on the way to work some morning.

Please keep the suggestions coming, if you've got any further ideas on what could be causing this.

 

Update: Just wanted to give a little update on my this issue. Sill no success in identifying the problem. I've been pretty busy with work, the last few days, so haven't had a whole lot of time, but here's what I've been able to do in the last few days.

Exchanged the Echlin/NAPA TPS. No change in symptoms.

Adjusted Brake switch again. All seems to be in working order there... I.E. when driving at speed, if I touch the brakes with my left foot, the Torque converter will unlock, and as soon as I remove my foot, it locks right back up... as long as my right foot is on the accelerator.

Have started going through the wiring, from what I believe, are the solenoids... looking for damage or wear, but am having some problems contorting myself to get a look at every inch. I'll have to pick up an extendable mirror or something to be able to see into all those deep dark places.

Next step: Unplug TCM and test solenoids... especially number 3. I'll have to try and find the wiring diagram for that. The one in my '96 FSM doesn't correlate with what is on my Jeep, so not exactly sure which pins are for which solenoid, but I'm sure the wonderful google will be able to help me out on this. I also plan on going through each and every plug I can find, inspect them for damage and give them a good cleaning.

I was also going to drain and fill the fluid, since I can't say with 100% certainty that it has the Dextron III in there. Not sure what the PO has done to it. Had everything ready to go this past weekend, but my wife's Oldsmobile started acting up. Turns out she crunched the lines running to the tranny cooler, so it was restricting the flow, big time, and ended up burning the fluid. Had to get that all sorted out, and her car uses the Dextron III too, so her's took priority over the Jeep and now I have to stop and grab a few more quarts of tranny fluid.

So, all in all, not a ton of progress, and no closer to figuring it out, but I'll keep working on it, as time permits.

 

Hey, does anyone have a picture of the wiring for the TCM on the 96 XJ?

My 96 FSM is showing the diagram for the 97 but it doesn't match up to what I have. I'm think I can use the 88-95 diagram, which I found online, but can't find anything definitive on my searches.

Took me a while to find it too. In my FSM it shows it under the dash, to the right of the steering column, but turned out I had to take apart the lower part of the dash (knee plate?), and it was mounted to the back of that on the passenger side.

Don't know why I bought this silly FSM... nothing ever seems to match up... well, a lot of things do, but 96 is such a bastard year, it is kind of annoying.

 

Alright... finally found the time to mess with the TCU. I had to track down a different wiring diagram, but once I got it all opened up, it became pretty self explanatory.

So here are my result from testing the ohms on the solenoids.

#1: 14.1 ohms
#2: 13.8 ohms
TCC: 13.2 ohms

So, from my understanding, all the solenoids seem to be within the expected range of 11-15 ohms.

I was really hoping that I'd find an obvious problem there, but I guess the search continues.

I was waiting to drop the pan, in case I had to replace the solenoids, but since that doesn't look like the problem, I'm thinking I might drop it this weekend and replace the filter and fill it with, what I know is, the correct fluid.

Like I mentioned earlier, I don't know what the PO has done with this thing, and it wouldn't surprise me if he filled it up with something other than the Dextron III. I know the new stuff is supposed to be compatible with the older transmissions, but I keep reading things on how they only like the original. I don't if Dextron VI would cause my symptoms, but since I have no idea how long its been since it was last changed, I figure it couldn't hurt to take this as my next step.

If anyone has any other ideas on what to look at, please let me know.

 

Problem Solved... I hope!

After taking a break from this issue, and messing around with some other things, I came across some info about adjusting the tv cable manually. I've adjusted it with the self adjuster a half dozen times, but decided to adjust in manually and make it a little tighter.

My first adjustment was to push the plunger in a MM or 2, and take it for a quick test drive. I immediately noticed it was shifting better, but was still getting the TC problem of it locking and unlocking while coasting downhill.

So, adjusted it another MM shorter (Pushing the plunger in) and took it for another drive. Shifted even smoother than the last time, and had no jumping from the TC locking and unlocking while coasting.

That was two days ago. Today, I had my normal 20 mile drive to work, lots of hills I end up coasting down, and where as I wouldn't call it 100% perfect, I'm satisfied with the 95%. No more jumping between lock and unlock, but there is still a slight hesitation when it wants to unlock. All in all, It drives like a completely different jeep.

The only thing I can think, is the TV cable is stretched and needs to be adjusted tighter than normal. With the end of it unhooked, its my understanding that the plastic clip should be just about centered with the post, when all the slack is pulled out of the cable. Mine now a good quarter to half an inch shorter, but it is difficult to tell the exact point where all the slack is out of the cable. Either way, it appears that the self adjustment on my cable isn't adjusting it correctly.

Stretched cable? Something messed up in the tranny? Its beyond me. So, wish I could explain why this solution is working for me, but I don't have the knowledge. All I can say is it worked. Thanks everyone for all the help and suggestions along the way.

Now... on to the next issue.

 

Interesting! Nice work. I haven't been noticing my rig doing it if I am in D. If I want to go in 3, is when I notice it happen sometimes

 

I bend the bracket on the throttle body to make them even tighter.

 

I know this is an older thread. but how exactly is the switch supposed to be adjusted? Is it supposed to be just enough for the pedal to be pressed that it disengages? or is it supposed to be pressed in so far? Thanks.

 

Push the pedal down a bit. Push the switch toward the pedal. Release the pedal. It's adjusted.

 

To test it:

Unplug the connector. Using a meter set on ohms, touch a lead to both wires. Push switch plunger in and there should be no continuity. Release the plunger, should be continuity.

 

I just bought a 95 cherokee... when cold it is fine, but coasting at 45 if I gas it again I get a little clunk, its pretty consistent right around 45... My first thought was to assume the converter locks pretty hard, any other ideas?

 

What does the fluid look like?
I would drain the trans. don't pull the pan...
Get a gallon of Dex/Merc fluid and replenish the trans.

also, CHECK THE TRANSFER CASE FLUID LEVEL. Same fluid is used.
Inspect your driveshaft u-joints also.

 

I've seen worse for transmission fluid, and at least it is full. I think I will still flush it while I am at a few other things (belts, front u joints...). I suppose it couldn't hurt.

 

Don't flush!! drain and refill only.
Check the transfer case!!