A fuel shutoff solenoid is located on the rear of the governor. There are two types. One is energized to run, the other is energized to shut down. The one shown is an energized to run solenoid. When the engine’s electrical system is energized (key on), the solenoid is activated and it releases linkage to allow rack movement in any direction (fuel on – fuel off). When the electrical system is shut off (key off), the solenoid is deactivated and movement of the rack is prevented in the fuel ON direction, causing the engine to shut down. A diode is connected between the two terminals of the solenoid. The diode eliminates electric spikes (high voltage generated by the coil of the solenoid when it is de-energized) that might damage other electronic circuitry in the vehicle electrical system.
- Fuel Ratio Control
- Mechanical Unit Injector Fuel System