Ive got '98 Mach Z 800 triple. Its not exactly stock. I put 3 brand new spark plugs in & start it. Seems to run fine for a few minutes then its like a cylinder drops off. I can take plug wire off 1 cylinder & it will almost die.put it back on and do same with middle cylinder, almost dies out. I pull wire off 3rd one and no change. Rev motor to 2100 rpms and slowly bring that plug wire to top of plug and u can hear cylinder engage & tach shoots up to 3300 rpms. But let motor idle and back to 2 cylinders. When idling poorly you would swear someone is sitting on sled turning headlight from dim to bright repeatedly. Also, dont know if this would be sole cause, but there is wetness around bottom gasket of this cylinder, but nowhere else. Any insight from u fellow Ski Doo guys would be so much appreciated!