DF40 hitting rev limiter

[Chad]

I need some help. I'm about to blow this motor up. I've got a Df40, I'm guessing 2000ish. Great motor. Anyway, took it out after having it sit for a year or so (ran in on ears first), and its hitting the rev limiter at 3k rpms.

Heres what ive checked.

I had an issue a while back with motor mounted neutral switch. Bypassed that one many moons ago. Have one on the controller anyway.

I have a parts motor motor I bought a few years ago. Swapped ECMs. Same thing happening.

Controller mounted neutral switch is operating...it will only start if motor is in neutral. So I don't think it's that one.

Ive "looked" at everything I can think of on the motor and can't find anything unplugged or out of place or broken wires or anything. Is there anything other than a neutral safety switch that would cause this seeing as I changed ECMs?

[Skunked again]

Try posting on marineengine.com. I've had some success their in the past.
Do you have a repair manual for it?

[Chad]

No manual.

[Macattac]

Have you got good water pressure? Stuck water flow sensor will do that

[Chad]

Don't have a pressure gauge but it appears good, which I know doesn't amount to crap. Lol. I'll check that. Thanks!

[billnorman1]

Have you got good water pressure? Stuck water flow sensor will do that

Roger. You may be hitting the limp home mode due to an overheat signal or flow issue if so equipped.
4 stroke, right?

[Chad]

Yep 4 stroke. It's not an overheat because the buzzer isn't going off. It does work. So I'm guessing it's a sensor of some kind because even when I changed the ECM, it does it immediately. I would assume (maybe incorrectly) that if it were a "problem" that was stored in the ECM, it wouldn't be there immediately upon restarting with new one. That's why I was thinking neutral switch possibly to begin with, or a short. I'll be home tomorrow and will check the flow sensor.