Boy, you're more patient than most people. The site went through some big changes last week and we're still getting used to it. There is now a list of unanswered questions and I don't see yours on it. Either your question was answered or something else happened. For a few days we were not getting automated e-mails telling us when replies were posted. That shouldn't have been a problem a month ago but for whatever reason, it got lost.
There's two different gas engines available for your Jeep. Both use a distributor that has a service bulletin related to drive gear wear and shaft free play. Based on the symptom I'd start by checking for a worn bushing for the distributor shaft and the air gap for the pickup coil. To have spark missing on two or four cylinders suggests the air gap is too big to generate a signal during part of the distributor shaft's rotation, or there is carbon tracking inside the distributor cap that is shorting out the spark to some cylinders. What we DO know is the ignition coil and module are working, however the ignition coil could be partially shorted and is not producing a high enough voltage for all of the spark plug wires. Those that are producing a spark would be real weak and would likely be the shortest wires.
If these suggestions don't pan out repost your question and include the engine size and any other details and observations. Thank you for your donation, but if you don't get this resolved, request a refund. I don't know the procedure but if you can't figure it out let me know and I'll contact the site owners on your behalf. They are very easy to work with.
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Thursday, April 18th, 2013 AT 2:10 AM