Speed Gradually Increases Or Decreases After Speed Is Set
- Ensure engine performs normally. Perform SPEED DECREASES ON STEEP GRADES OR UNDER HEAVY LOADS test. Ensure accelerator pedal and linkage open throttle fully. Go to next step.
- Check vacuum dump valve. See VACUUM DUMP VALVE TEST. Service vacuum dump valve if necessary. If vacuum dump valve is okay, go to next step.
- Check servo. See SERVO TEST. Tap servo body lightly while testing. Replace servo if defective. If servo is okay, perform AMPLIFIER TEST.