MustanGTyler

Hello all,
I just purchased my first jet ski. It's a 1998 SeaDoo GSX Limited. I came from the motocross scene and am studying to be a mechanical engineer so i'm very mechanically inclined. I'm 15 and my father and I were looking for a project so we picked up this ski knowing it is not in proper working order. It seems to have some sort of electrical issue creating weak spark. when you ground the plug and turn the engine over, the spark is barely visible and sometimes even nonexistant. i checked the compression and it is fine. The previous owner has went through and insured all the grounds are correct and even went as far as adding additonal ground wires all over the place. He also replaced the coil with no luck. Where should i start looking for answers to this mysterious problem? Any and all replies are welcome and I appreciate your help.