In the 6 months that I've owned my XJ, this anomaly has occured 4 times. Each time, I start the motor it "runs" like the firing order is incorrect. Each time, I immediately shut it down an tried to restart, which it did and purred like a kitten. I've been searching for answers but have come up pretty much empty. BTW, there isn't ever a driveability issue after the restart.

A former Jeep tech at work told me it might be the CPS or a distributor issue but was only taking a stab in the dark without actually seeing the vehicle.

I would like to nip this issue in the bud if I could find exactly what it is before it becomes a larger issue. Any ideas?......

This is a XJ Sport 4.0L

 

I know exactly what you are talking about. Once in a blue moon it just starts up like it's running crappy and wants to die.

It's rare but I have come across it as well. No leads here either...

99 4.0 sport 4x4 auto.

Weird stuff

 

Just brainstorming that it could be a camshaft position sensor issue; they control the timing of the fuel injectors, as well as other things. It is located inside of the distributor.

Makes it very difficult though when this is a very "intermittent" issue.

 

Does this only occur on a hot day after you have already been running your jeep?

 

To the best of my recollection, it has happened only after running (read - warm, operating temp).

 

It could be heat soak, that happens on "newer" cherokees. The heat of the engine combined with the heat of the outside air is enough to boil the gasoline in injector 3 when you turn your cherokee off. So when you go to start it up when the engine is still hot the gas has not reliquified and no gas is getting to the third cylinder, causing it to misfire. It takes about 20-30 seconds for new gas to get to the injector and then the misfire will stop. Try wrapping the third injector in heat reflective tape to keep the sitting gas from boiling. I did it to mine and haven't had any problems since.

 

Mine does it too. Chyrsler had a tb I think a while back and the dealers would install a cheap tin heat shield. Mine has it but still does it once in a while (today) when it's hot outside. I just make sure I get moving quickly and it goes away. If you idle too long when it happens it will give you an error code of cylinder 3 misfire.

 

I think you might be onto something. The more I think about this, the more the heat soak issue makes sense. I found the TSB on this and I'll wrap #3 injector with heat reflective wrap and see if this resolves the problem. Thanks for the heads up.....