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 1400-1750 RPM. When throttle switch closes, system will operate until engine speed decreases to 1300-1475 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.