Mixture Control Solenoid - Slow Cut: Description and Operation

Fuel (Slow) Cut Solenoid:

The fuel cut solenoid is also referred to as the slow cut solenoid and coasting fuel cut solenoid. It is an integral part of the carburetor. When the ECM detects a deceleration condition via inputs from the idle switch and MAP sensor, it signals the fuel cut solenoid to close and cut off part of the fuel in the slow circuit of the carburetor. This prevents catalytic converter overheating and after burning in the exhaust system.

The ECM de-energizes the fuel cut solenoid when these two conditions exist simultaneously:

1. MAP sensor signal vacuum is less than 308 mmHg absolute.
2. Engine speed above 2000 rpm.