The Fuel Shut-Off System was introduced in some 1980 B310 USA models. It leverages the anti-diesel valve to stop the fuel flow during periods of deceleration. This is similar to what EFI systems do. It is only active at higher speeds, namely above 40mph.
1980: All California models 1980: FED A15.MT 1981 CAL, FED, FED.MPG and CAN.MPG models. Canada models did not use fuel-shut off except for MPG (FU Engine) models.
For safety and good performance, the FSOS does not work unless the engine is decelerating.
- Only works when decelerating (vacuum is high AND speed above 40mph)
- Does not work in nuetral, so engine will not stop due to lack of fuel
- Does not work when clutch is engaged (so you can blip the throttle)
- Anti-diesel valve (solenoid)
- Vacuum valve
- Speedometer speed switch, amplifier and relay
- Also used by CAL Mixture Ratio Rich-Lean Exchange System
- Automatic Transmission inhibitor switch
- Manual Transmission nuetral switch
- Clutch pedal switch
This would be an interesting system to retrofit to older models for increased fuel economy.