HI all -


I I have a 1996 Jeep Grand Cherokee – 4L straight six with 4speed Auto – duel range 4h/4l.


The jeep runs very well until I take it of road – off road it performs very well, the auto does very well and I am very surprised where I can take the jeep – However the problems starts when I come back onto the tar -


When I put it back on tar – The jeep will not tolerate any loading at all – what I mean by this is when the jeep kicks back a gear – it becomes retarded and try s to stall – it's like it has a lead that has popped of the head or something.


The engine idles well and if not under load is smooth - and will step through the gears nicely – no clunks or bangs... but go to load it up – like kick it back and give it some curry– then the issue starts


Here's where it gets weired – When this happens and I pull up and stop for about 20 to 30 minutes the jeep goes very well after it has rested and problem seems to go away. The temperature stays steady at around 100 on and off road -


I think there may be a sensor/switch/solenoid that may be playing up when put under pressure in 4wd low and it might be stuffing around with engine management system -MAYBE?


I have replaced leads/plugs/fuel filters – The distributor seems all OK and has no moisture or cracks in it – and all contact points are clean and tidy.


I have had a good look under the vehicle and all looks tidy and in place – so no sign of damage at all -


I cant seem to find a second fuel filter - does it have two or one – replaced the one at the rear near the tank -






Any ideas pointers/solutions and/or fixers would be appreciated -


Regards
Danny


PS...... did the dashboard diagnostic and it came up with code 37 – which means toque converter issue – I think this may be wrong – course the gear box works very well and changes nicely.

sounds to me like it may well be the torque converter, its just weird that it dosent happen all the time... How many miles does your xj have? Ever replaced the tranny or converter before?

The unit has 148 thousand kilometers and I have never done a transmission – I have only had this unit for like 3 weeks or so. The jeep now is working superbly – no retardation or or anything – just goes grotty when I get back on the tar -


Is there a solonoid/switch that might be playing up? Only happens when a play on the off road side -

Hi Danny, Is this the Temperature reading you have at the dash, or have you found this a different way?

The coolant temp sensor on your vehicle has two functions 1)send info to dash for engine coolant temp, and 2)resistance value to the pcm for the proper fuel injector pulse. If this sensor is reading 100F then the pcm thinks it's a cold engine and inreases the injector pw, basically loading up the engine which will cause it to run poorly under load.
The check engine code you retrieved "37" Is for the torque convertor clutch solenoid , history issues I have seen with this model and year is a shorted TCC solenoid which results in bad fuel mileage(like in a jeep that can be seen...LOL) and long acceleration times from 1 gear to drive, and slow passing acceleration.

Hi ***** – thanks for your information – The heat reading I am quoting is from the Dash -


I sort of knew the the Toque Converter is ok – I suspected a switch/solenoid had an issue. You have to forgive me for my ignorance but I am new to the jeep world and still coming up to speed on models etc....


I was wondering if you might know what the gear box model number on the Auto would be – also if I may push my luck possible part numbers for the solenoid ….


Model – 1996 (right hand drive) Grand Cherokee – straight 6 – 4sp Auto...


Again Thanks ***** … owe ya a beer … appreciate the information...
Regards
Danny

You know, I've had this happen to me twice in the last year. Last winter, after wheeling in the snow for hours lots of 4lo time. Trying to climb out of a ravine, it suddenly acted like there was something plugging the exhaust. I didn't shut it down, and it behaved like you mention on the highway.

Second time was a couple weeks ago, just doing some desert roads. About an hour. No 4x4. Got on the highway to head home and it was behaving as you mentioned...

Both times, I got home and shut it down, started back up again and drove it and it was just fine again. NO CODES!!! But I am hesitant to shut things down and restart on the trail. I would describe the feeling of the problem like hitting a rev/speed limiter, but at 2500 or so RPM...

I know your gonna think Im crazy, but it sounds like the t-case to me. In a 96 you should have a NP242, these are notorious for killing viscus couplings. It works a lot like the torque converter, but is in side the t-case. A friend of mine was having this same problem, we replaced the t-case with a NP231 and the problem was solved. The VC will "lock up" and it will put the engine under load. It will also cause a hesitation while driving. It's almost like the trans goes into neutral for a second, and then kicks back into gear. When in low range the VC is locked up, in hi range it's free spooling so you get 2 wheel drive but will engage if needed. Just my $.02, you never know.

So at the end of the day – did you end up finding out what the problem was?

148000K's