Ok well, to start off I'm new to this forum. I've nver owned a cherokee but have had many wranglers. I have never had an auto trans, and this thing is giving me a head ache!
So to details... 87 cherokee, aw4 trans. 250000 miles. I was told jeep sat for about 6 months. motor has an oil leak that I'm in the process of hunting down. I think its around the funny looking thing the filter screws on too. Here is the problem... When you first start the jeep to go somewhere it will not shift out of first gear for about 10mins. Then all of a sudden it will start shifting and will run fine. Then you get to work, after work you get back in it and it will do the same thing, 1st gear for about 10min and then will run fine. Well today I changed out the tranny fluid and filter. Added a little lucas oil addative to it. Same dang problem!
I was reading a few threads about throttle position sensors, but they seem to stay in 3rd or 4th gear. Any one ever had this problem? tough times and this is my only form of transportation.
Thanks!

 

From the sounds of it it could be a couple things:
TCU
Solenoid
or wiring between.

 

TCU? which Selonoid? what wires should I check?

 

Transmission Control Unit
1st/2nd gear solenoid (inside trans)

Im not sure on wires to the solenoid, Ill have to look them up.

 

ok so update!

this morning went out side and found the TCU. Unplugged it and dorve around for while shifting manually. Of course the only gears i had was 1-3-D. But everything shifted fine. And have a the trusty old 4.0 had plenty of torque when i needed it in 3rd.

So what should i check next?

 

Unplugging the TCU bypasses that and all the solenoids and the NSS...

Everything you need to know!
I have replaced my TCU and 1 shift solenoid since i owned my jeep.
http://www.transonline.com/transdige...ers/index.html

 

Superman, my XJ does the EXACT same thing, I've found that letting it warm up for a few minutes before taking off and driving sometimes eliminates the problem, also with mine it stays in 1st until I get it up to 3K rpm, then quickly let off the gas and it'll shift into 2nd, usually does this once or twice until everything gets to operating temperature. I also changed the fluid/filter and added a quart of Lucas to mine as well, to no avail. When I first got it, I took it to a local "Meinekee" to get a tranny flush, they insisted on taking it for a test drive, and when he got back, the guy told me my tranny was shot and needed to be replaced, that was about 15-20K miles ago and over a year, it hasn't gotten any worse or any better since I first got it. My mechanic buddy told me that he thought it was more than likely just a gummed up solenoid, and that if it didn't get any worse it wasn't anything to worry about. So, if you find out how to fix it, let me know man, I'd appreciate it,lol, but like I said, I've put quite a few miles on it and had it for a while,so I wouldn't let it worry ya too much bud.

 

Thats the one Ive posted before, but couldnt find it. Page 3 will tell you what pins to use to check the solenoid. It should be around 12-15 ohms resistance.

Heres a writeup on replacing the solenoids:
http://www.naxja.org/forum/showthread.php?t=987463
for a 97, but theyre all pretty much the same inside.
Replace solenoid, as posted above.

 

that doesnt make sense, why does it still shift manually if the TCU is unplugged?

 

Gears 1 and 3 are defaults (thats what you had manually shifting, 1 and 3) and do not require any input from the solenoids or the TCU, it is done with the valve body in the trans.

 

so before dopping the pan and ordering selenoids, how do i cancel out the TPS and/or TCU?

 

http://www.lunghd.com/Tech_Articles/...iagnostics.htm
Scroll down to TPS, it will tell you how to check it

You can try a TCU from a different Jeep 87-89 if you have any friends with an auto from those years.

If the TPS and TCU are fine, it is most likely a solenoid.

 

AW4 TRANS SERVICE
http://go.jeep-xj.info/HowtoAutoService.htm

AW4 TROUBLESHOOTING GUIDE
http://members.fortunecity.com/90limited/

General AW4 INFO
http://www.novak-adapt.com/knowledge/aw4.htm

AW4- under best auto trans http://www.off-road.com/jeep/cheroke.../jeepspeedfaq/

AW4 TRANSMISSION OVERRIDE SWITCH
http://www.jeepbarracks.com/modules...=article&sid=19
http://www.go.jeep-xj.info/HowtoAutoSwitch.htm
http://jeepforum.com/forum/showthread.php?t=234510