97 Grand Cherokee Laredo 4.0 ltr 4x4 will not shift into overdrive.

[valey0531]

Hello everyone, I have a 97 grand Cherokee that is currently giving me some drivetrain problems. I have a code that keeps coming up that states that my circuit input is either to high or low to my throttle position sensor. I replaced the sensor and it keeps giving me the same two codes, sometimes together, sometimes separate. The actual problems that I am having is that it will not kick into 4th gear, or overdrive, while I approach cursing speeds. I tried using the OD OFF button on the dash but it does nothing. When the engine and trans gets to the speed where it usually shifts into 4th, it jerks like it wants to shift but stays in 3rd. I have consulted with some techs on the matter but they say that either there is something wrong with the wire and plug for the sensor, or the power train control module is malfunction which could lead to the transmission control module to malfunction and the reason why it is not shifting. Also, when u put it into drive and move at slow speeds and then come to a stop, it almost stalls and the battery gauge dips down. Sometimes it does stall and takes forever to turn back over. Any help on this matter would be much appreciated because I need this vehicle to last. The engine however does run strong for having 182,000 miles on it. The trans does shift perfectly fine between 1,2, and 3 gears. It just will not go into OD. Let me know guys, thanks!!

- Kyle

[SteelHeadz]

Does it do it only when the lights are on or any other loads? or is it all the time regardless?

[valey0531]

Does it do it only when the lights are on or any other loads? or is it all the time regardless?

I do not believe it matters what is on. It seems to do all the time regardless what else is on. Any ideas?
-Kyle

[SteelHeadz]

I would recommend that you check the TPS sensor connector for corroision or a poor connection and likewise for the PCM connectors just to verify that it's NOT as simple as that. There's a possibility that the governor pressure sensor could be malfunctioning as well causing the symptoms.

[Appleshack]

This sounds really simple and I'm sure you did this, but I had the same exact problem and I put some Lucas in and the tranny fluid was low. Topped it off and it seemed to fix it.