I have a baffling ignition problem on my Mule 1000. The problem started with one of the cylinders missing. I pulled the spark plugs, which were pretty new, and they looked fine so I cleaned them up and put them back. I also replaced the spark plug wires as they were still the originals. When I started it up it was still missing. Next I switched the two spark plugs and tried again and the opposite cylinder was missing. That told me it was a bad plug so I replaced both plugs and it ran just fine. Problem solved... or so I thought.
About 2 weeks later it started missing again. As I was determining which cylinder was missing I made an interesting discovery. When I pulled one of the spark plug wires the cylinder started firing briefly as I removed it. I found that if I left the wire very loose on the plug it ran fine. I left it that way to see what would happen. A few days later the other cylinder started missing. Same thing. I used it for a while with both spark plug wires very loose. Eventually it started missing again and finally wouldn't start at all. With another new set of plugs it again started right up but it wasn't long before it was missing again. I pulled both plugs, grounded them with the spark plug wires attached, and ran the starter. One fired and the other didn't. Then I pulled the plug that wasn't firing away from the ground while running the starter. When I got about 1/8 inch away it started firing, also sparking between the plug and the ground.
I changed brands of plugs to the exact NGK plug recommended in the manual. Again, after running fine for a while it started missing. The plugs are not fouling, just a very light coat of black carbon. I have gapped the plugs to specs very carefully. Once the plugs stop firing they seem to be permanently ruined. No amount of cleaning will make them work properly again, although they will always fire at least for a while with the plug wire loose so that it is not quite contacting the plug.
My nearest Kawasaki dealer is as baffled as I am. I hate to haul it in for repair if it is a simple fix. The dealer says the electronic ignition module can't be tested, but the first thing he would try is replacing that. Unfortunately, he wouldn't know whether it fixed the problem until I used it for a while, and at that point I pay for it whether it helps or not. If I am going to try that I might as well replace it myself, but I would like to be pretty sure that's the problem before I spend the money.
Any thoughts? Many thanks.
