yamaha f225c RPM problem

[acpet]

My Yamaha F225c has no problems below 4000 RPMs but as I increase the throttel it begins to increase the RPM but abruptly starts to run rough and drops to lower RPM. After many trials I can ease the RPM higher to get it to run at 5600 RPM. I have a water seperation filter installed and water dosn't seem to be the problem. Is there some sensor that could create this problem.

 

[rodbolt]

Re: yamaha f225c RPM problem

no sensors that will do it but a dirty VST filter or a fuel line restriction can.
its a fairly normal issue VST filter cleaning/inspection is supposed to be every 200 hours OR once per year whichever occurs first.
keep dogging it running lean and you may get to post about holes in pistons or melted exhaust valves, the V6 F motors did not use a knock sensor.