Fuller

Hey guys I have a 2005 kodiak 450. It was running and working fine when suddenly one day the starter button wasn't working it pull started fine for a couple days. Until I had time to look into it I took the switch apart didn't find anything crazy. So I put a bump starter across the solenoid and it cranks great. But never would fire. Pulled the plug and I have no spark. I'm wondering if the cdi box could be causing this issue thanks