Ive got a 97 zrt 600 and i cant figure out why the middle cylinder isnt firing. ive changed plugs two times nothing. Ive put a spark plug in the boot and pulled it over and there is spark in the middle cylinder. when you pull it off the plug the motor doesnt change, but you pull the boot off one of the side cylinder and it dies. so i dont know what to do. anyone have any ideas. thanks!!!!