a little update on this. I cleaned the plugs, they were quit black. started it up, and it ran very good on the right mag. left mag, ran like it was not on all 4. problem is in the ignition. I had my spare cdi and installed it on the left side. switch that is. not sure at this time which coils that one runs. will find out though. I have the rotax heavy duty manual so I have the wiring diagram for this. I replaced that cdi about a year ago with a soft start. the original cdi quit working when cold. installed that cdi and ran the same, so it is working. I am starting to think coil at this point. I need more time to dig in and find the problem. let you know.