Is this the 4th of July!!!!!

[pvt.Tadpol xj]

Extreme Caution..No joking around on this one..... OK? I have had a rough idle with my 1991 XJ. Even after installing a new ignition kit. So one night after work around 9:00 PM I pulled my XJ into my garage Where it is really dark, and left my 4.0 running and opened the hood. Of course I had a flash light.Now i turned out any lights and very, very, very, Caerfully looked around, and low and behold I found heavy blue sparks in three diffrent places where my plug wires were touching pieces of my A/C parts. So i crawled under the front very,very,very carefully, and found heavy blue sparks jumping from my alternator over to my ignition coil. OK, OK.. I cured this fireworks display by wrapping these places with some black tape and then some plastic wire loom on top of the tape.And it really works......

[Mudderoy]

Other than listening for "clicking" or "popping" noise dark is the best way to find shorts in your ignition system.

[BlueXJ]

I think I have posted that trick on one forum or another. Usually a new set of plug wires will cure the spark jump thingie.