Deceleration Fuel Cut-Off System: Operation
Deceleration system relay is activated only when coolant temperature is above 113°F (45°C), time relay is activated and engine speed exceeds 1400-1750 RPM. When throttle switch closes, system will operate until engine speed decreases below 1375F75 RPM.
During system operation, airflow is directed through by-pass hose and vacuum valve instead of passing the airflow sensor plate. Airflow sensor plate then closes which cuts off fuel supply to cylinders. See Fig 1 .