Texety

This is in relation to a 1998 ZJ - Jeep Grand Cherokee Laredo 4.0 2X4. ---

Jeep will do 1 of 3 of the following upon start up, sometimes will switch from 1 issue to the other while running.

1. Engine stalls at low RPMs, such as approaching a red light. Sometimes when giving 'too much gas', the engine will hesitate and makes it extremely difficult to gain any speed. When started, RPMs shoot up to 2,000 idling.

2. Transmission will not shift from 1st until 4,000 RPMs, whatever gear it then shifts to it remains in until it down shifts to 1st again.

3. Not an issue.. But the Jeep will drive, shift and run perfectly normal with no issues.

Note that almost never, if ever do these issues occur at the same time.

Got the CEL codes read and came back with the following;

P1762 - Governor pressure sensor offset voltage too high or low.
- ECM detected the offset voltage was out of spec for more than 3 seconds
Probable Cause
- Internal Trans Failure
- Open or shorted circuit condition

P0123 - Throttle Position Sensor
Probable Cause
- Check Connector and wiring to sensor *(Looks fine to me)
- Sensor open or shorted internally *(Have not tested. But did unplug while idling at 2k RPMs, and RPMs dropped to normal)

P0108 - MAP (Manifold Absolute Pressure) / BARO or MAF (Mass Air Flow) Sensor Condition.

(P0108 is the one that throws me for a loop)

Now i do find it interesting that the stalling and such could be related to the P0108
The Excessive RPMs at idle is related to the P0123
The Trans shifting issue is related to P1762

My questions....

Went over a BAD bump one day that caused all this (did not bottom out or anything)

Is it possible that any of the 3 are linked? Fixing 1, may fix the other(s)?

P023 and P1762 hopefully would be an easy enough fix, but i dont even know where to start with p0108 other then checking to make sure all the hoses are not cracked and are attached properly... Does anyone have any insight on this?

Furthermore, I am hoping maybe someone has had the same issues and could give me some more detailed help.

A little disclaimer that may or may not be related, the Jeep has had some battery drainage issues. Not sure if it is still happening, or if it is related to any of the CEL codes, but i feel it should be brought up.


Thanks for any help.

hunter1a

The Torque Converter will cause some weird stalling problems. I have a 42re in my 05 GC and before I pulled it out it was stalling the motor sometimes. I had a LOT of problems that ended up being all Trannie related issues. After I got my Trans. out and opened up I was really surprised at how much abuse my Transmission took and kept moving !