TFD 247

Hello all, I am new here and could use home help from some Jeep experts. I recently got a 1997 Grand cherokee with 167K miles on it that had tranny problems. It won't shift out of first gear sometimes. For the first few minutes of driving it, it will upshift at around 2500-3200 RPMs depending on how fast I accelerate. But after I drive it a bit, it progressivly gets worse, it will upshift at around 3200 RPMs if I accelerate very slowly, then a while after that, it won't upshift at all. I checked the TPS and the volts go down slowly as I open the butterfly valve, so I think it's not the TPS. I put the car on jack stands, and put it in drive, it shifted up right at 2000 RPMs. This may have been because I shut the car off, then put it on jack stands, but I don't know. The only other thing I tried was to see if (name slipped my mind right now) the cable coming off the butterfly going to the tranny was stuck, it isn't.

So to recap:
-upshifts out of 1st at high RPMs
-progressivly gets worse
-Shifts fine from 2nd to 3rd
-once the motor is restarted, the process starts over.
-Not TPS
-Not cable to tranny.

Any help is appriciated! Thanks in advance.

tiwvr1

I am thinking that it is a mis print, but the voltage should go UP slowly on the tps as you open the throttle. At idle it should be AROUND .70v and at full throttle it should be close to 5v

TFD 247

No, closed throttle, I got 5v, then slowly opened the throttle and exit voltage went down. Maybe because I measured the middle wire and wire closer to the left fender. Is that bad?

candymancan

Almost sounds like what mine would do when the fluid needed changed, or when the output speed sensor needed replaced.

jack1981

i think there was a recall on this to reflash the pcm at the dealer. try that as i think it should solve your problems.

biggoofy

I would lean towards a fluid / filter change and a band adjustment