f250 idle revvs and rough operation at 700 rpm

[karlmenard]

I have the 4 stroke f250, 2008, with about 1500 hours on it. It has been flawless until today. The engine starting running very rough at 700 rpm when slowing down to *****. I set it in neutral and it starting to rev up to 1600 and even as high as 2200 by itself, it was dropping and rising various rpms with no control by me. I put it back in gear and it ran fine, even at 700 rpms. then I got back to the dock and tried to switch from forward to reverse at idle and it started revving on it's own again making a hard transition to reverse and almost causing a wreck at the dock. Please advise.

[rodbolt17]

that engine uses an acceleration sensor to activate the throttle plate motor.
you need to get it hooked up with a laptop and see what the sensor and TPS are doing.