Ive noticed randomly that my 01' XJ stumbles at idle sometimes after start up when its hot. Ex) Drive it to gas station, Turn it off, put gas in, turn it back on 5 mins later). And it doesnt happen all the time, only randomly. It will stumble for maybe 10-15seconds then stop and all is well. Still, it feels like its gonna shut off, and Id like to resolve it before it gets worse. Only thing I replaced since owning it is radiator and thermostat even though it didnt need one. Also new spark plugs. But it did it even before the new plugs. Also its the coil pack ignition, not distributor, any ideas?

 

Just an outside chance, and really easy to check. On mine where the injector wires come up from the front, the gang comes around the manifold heat shield. That shield was into/grounding some of the wires sometimes. Only took 1 1/2 years and 6 in of tape to fix it!