My problem is that my watercraft seems to speed up and slow down and high speed. It will idle just fine with no throttle. When I am at top speed it will jerk back and forth all the time. The RPM's will jump from about 7000 rpm to 5800 rpm and so on. It is really annoying. I'm thinking maybe its a fuel mixture problem or an injector clogged up. I have a 2nd identical Sea Doo that works just fine. I have fresh fuel and oil with new spark plugs. I have run Gumout through this and it did not help. So please help!! I'm trying to sell these after being out of work for 4 months.