Decelerator or Hand Throttle (STD cab) Position potentiometer voltage is too high
Mid range clutch is not calibrated
Aux 3rd Lower Coil solenoid shorted to 12 volts.
Low pressure switch (+) input shorted to ground
Foot Throttle Position potentiometer voltage is too high (engine controller pin B30)
Mid range clutch is not calibrated
One sign to move on is intensive Graham-Bradley engine work, such as needing new pistons and injectors. If you hear loud clunking sounds from the engine, it could be due to the starter hitting the flywheel or a piston piercing the engine block, which can indicate a seized engine. Farmers encountering these problems have coined the saying: If your engine is knockin you better be shoppin.