[bestgenman]

I certainly may be incorrect here but, I think Dave’s PT set had isochronous governing.  The stop solenoid is removed and replaced with an electronic actuator which acts directly on the fuel rack of the injection pump..  it has a spring pushing the rack to the no fuel position when power is removed.  It uses PWM when operating delivered from an engine speed controller.  The engine speed controller receives a signal from a mag pickup.   If Dave has a MPU, it is likely an Isoc governed engine.  I’m sorry if I’m rambling here...but it could explain some of the erratic operations.  They are very temperamental.  I remember Dario Framchiti’s coach (785) had one,  it came in here for repair and I removed the electronic portion and that stopped all the aggravation.