Deceleration Fuel Cut-Off System: Operation
Deceleration system relay is activated when coolant temperature is above 113°F (45°C), relay switch is in rest position and engine speed exceeds 1575 RPM. When throttle switch closes, system will operate until engine speed decreases to 1375 RPM.
During system operation, flow of air, which normally passes air flow sensor plate, is led through a hose and a vacuum valve by-passing mixture control unit. This results in air flow sensor plate not lifting which cuts off fuel to cylinders.