Originally Posted by Hotroddinlogan

So I have a 4 door 2000 Jeep cherokee sport, with coil on plug ignition. And I has sat started on the regular. So just about a month ago I started it, and recorded it for my Youtube channel Hotroddinlogan ran it for about 15 minutes. And all of the sudden she shut off. It ran buttery smooth and didn't knock or shake. Just died out of the blue. I did not attempt to start it until the next morning. It did not want to start again, even at wide open throttle. Didn't even try. We have tried starter fluid with brand new autozone spark plugs. Again, didn't even try. It did not say on the dash "no bus" so its not the cpm. We did a spark test, it had spark but we are not sure how good the spark was in the broad daylight. But it did have some kind of spark. We have the spark plugs gapped to the stock gapping 0.35 and we have good fuel pressure. Help! This is a head banger.

Originally Posted by Hotroddinlogan

How to replace a headlight

This is the last time it was seen running ok. I'm starting to think to is one of the three coil packs (aka the coil rail). We tested it with a really hot spark plug. It did have spark though. The last time it ran, it ran funny. It started no problem, after it ran for a couple minutes. But, the engine was hesitant to rev anywhere above about 1100 rpms. Than 5 minutes later it was hesitant to start. In fact, it didn't even run long enough for the starter to disengage from the motor's ring gear. That should be saying something. I later made a video for a school project and it ran. Again hesitated to rev up. Now above just about 2000 to 2500 rpms. But this time didn't think anything of it. I always heard these Jeep Xjs tend to fix themselves lol. Than off camera it shook for about 4 minutes and stopped. It then ran buttery smooth for the next 10-15 minutes and than died out of absolutely nowhere.

Originally Posted by XJ_XJ

You probably know more than me. In my experience no, Jeeps do not fix themselves, in fact I tend to make mine worse working on it.

Originally Posted by Dave51

Which fuel pump tester did you use? They can vary in accuracy.

So you sorta have spark, and sorta have fuel (pressure anyway). As noted in your response to another thread did you test these?


Do you have a multimeter?

Although hopefully the codes should reveal something. Are they still there or are they transient? My WAG is it's going to be a 1391. You should be able to monitor oxygen sensor activity with the ELM327 software.