My Aquatrax started missing at idle last season and got progressively worse. It would run on 3? cylinders and then suddenly rev up . It made steering very problematic as it would start to oscillate back and forth - you had to get out of the throttle for fear of spilling. I've changed the spark plugs although I feel it is most likely is a fueling issue. Could dirty fuel injectors cause this condition? Any ideas? I've also purchased a new fuel filter, but after buying a factory manual, find fuel filter replacement isn't even covered! My aquatrax has been well looked after (oil changes, greasing, and fuel stabilizer etc.) and not abused and has only 40 hours total use. I've just started it up with the new spark plugs and the misfiring condition is still there. HELP?