fast idle, slow reverse-200hp 2 stroke yamaha

[JEF]

hello
I took the boat out today for the first time and the 2002 2 stroke Yamaha 200 hp engine seemed at first to be missing at high rpm. Maybe an hour or so later I noticed it would intermittently go into a fast idle which made it impossible to change into gear without a jolt. Also, reverse would not go above idle speed. The fast idle was about 1700 or so RPM. I added oil and it didn't seem to change though later- 45 minutes or so- a regular idle reappeared by which time I was just about ready to take the boat out of the water. Could this be oil related?

[boats.net]

It could be stuck or sticking throttle linkage.If it's a EFI model the ECU may be advancing the timming. It gets its signals from all the sensors on engine to control timming, which would mean it needs to be tested.