HELP!!!!! We have recently obtained a 1987 Jeep Cherokee 4x4 with the 4.0L Inline 6. We are using it for mudbogging and cant seem to keep it running. We thought it was overheating but have determined that the water temp gauge is not working properly and it is not overheating. We replaced the thermostat and have flushed the radiator just to be on the safe side. As soon as the engine is getting warm it is coughing and backfiring and losing all power. It will start up again after sitting for about 10 minutes. We have had suggestions ranging from we need a new fan to we have a PCM (power control module) going (or gone) bad. Looking at the Chilton manual it is not supposed to have a module. When we had the distributor cap off we did notice there to be a lot of oil in the distributor. We took that off and cleaned it out and the problem is still there and is getting worse by the minute.
Any suggestions?????
My husband is about to yank his hair out!! And any help would be appreciated.
Thanks in advance,
Chris and Brad

Not sure, but I would look into replacing the distibutor. If oil is getting into it good chance the stator damaged. You could have a cracked head, but the distributor would cause all of your before mentioned problems. I'm not sure if it'll work in the XJ, but I have an 86-CJ-7 that is using a Ford ignition system, might be an inexpensive alternative.

I've had two jeeps that have done the same thing, an 89' cherokee and a 92 cherokee. My problem was a sensor that hooks up somewhere near the intake manifold and tell the computer how to choke the engine. Then problem is when it goes bad it starts to flood the engine because it wonts to choke it all the time, like it has just been cranked. I cant remember the name of it right off hand but give me till a little bit and it will come to me. However the sensor is like 30$ at any parts store, so its not that bad to replace. when i think of the name ill come back on and post another reply for ya if you still need help.

Thanks guys...so far we have not figured out what it is. We are looking into the EGR valve right now, but that is looking rather pricey (and unnecessary) so we are trying to find a way to bypass it. Stang...if you think of what its called please let me know. And thanks Mud...I am thinking a new distributor is going to be in the works either way:)
Thanks again guys...and again...any more ideas are always welcome. Will let ya know if we get it fixed.
Chris
CBC Racing

Would that be the O2 sensor???

JD

No, Stang would be talking about the MAP sensor.

If you want to bypass the EGR valve, just look to see where the exhaust line goes back into the intake, unscrew it and cover up the hole with a piece of carboard.