My ZJ has had a misfire for about 2 months and I can not figure out what the problem is...
I changed the plugs, wires, distributor cap, rotor button, twice.
The plugs were gapped properly both times. Checked and rechecked the plug gap also. The wires are all pushed on tightly and matched to the proper cylinders/firing order.
I thought it may have been bad parts so I got different brands the second go around. I've tried every combination between the parts new/old and nothing seems to fix the misfire.

Is there anything that I may be missing?

 

what cyl is it missing on? What year? how many miles? Any other codes? Does it miss at idle, or while driving? Does it miss all the time, or just when it wants to? Lots of questions need answered.

 

The engine is the 6 cylinder.
Its pulling a cyl 1 misfire code and a multiple cylinder misfire code. It has 190k on engine. Also pulling a transmission voltage code. It seems to only miss at idle it drives fine usually. Sometimes you can feel it when its low rpms.
To help describe it, when the transmission is in gear at idle with foot on brake it will misfire.

 

Do a compression test, wet and dry, to see if you have either a valve issue or a ring issue. If that all checks out, swap a few injectors around and see if the miss changes cylinders. Injectors do not fail very often, but they can.

 

You mentioned you changed plugs, the other day i did the same thing on my ZJ. I put AC double platinum in the 4.0. When i fired it up it had a miss cold at idle that cleard up when i started driving it. I posted here about the problem and a member told me to change the plugs to copper core. Although skepticle i did it and that was the fix. No more miss idles fine no issues. If you didnt use copper core i highly recommend getting them and make the change.