Transmission Problems please help!

1996 cherokee 4x4 4.0

My jeep started slipping while i driving it about a week ago. I was going about 45 and all of a sudden it was like someone put it in neutral. It was still in drive though. I stopped, put in in park and then drive again and it was fine. Got home checked fluid, it seems fine. This happened once more the next day and on the way home it downshifted to 1st gear while I was slowing down to make a turn. I had to drive the rest of the way home in 1st gear. It was only about a tenth of a mile thank God. I researched it here and alot of people that had about the same problems suggested to replace the TPS throttle possitioning sensor. They said somthing about adjusting it. i never did figure this out???? I repleaced mine for $25 and never saw hoe to adjust it. It just had 2 mounting screws and wires that plug into it. Mayeb this is my problems i dunno. Well then after I replaced this part it seemed ok and so I decided to have my transmission filter replaced at a local shop that I trust. They replaced it and I drove it for a day. Then on the way home i am pulling a 5 X 10 trailer that is empty, and i goto take off from a light and the transmisison is in 3rd gear I. I stopped put it in park, then drive agian and it was still in 3rd gear. I slooooowly took off and came to next stop sign and it did downshift to 1st. I made it home and here I am. HELP what do i need to do other than putitng in a local shop that will rebuild my transmission reguardless of it needing it or not. haha. ANY help would be appreaciated. Thansk in advance! ---- TJ

Check your MAP sensor and the vacuum lines going to it. These could cause your shifting problems.

Mike

Where is the map sensor located?

3rd one down.

http://www.lunghd.com/Tech_Articles/Engine/Basic_Sensors_Diagnostics.htm