Controlled Catalytic Converter (C-4) System: Operation: Carburetor

Carburetors used in conjunction with the C-4 system are designed with an electrically operated solenoid in the fuel bowl. In the Rochester E2SE carburetor, this solenoid provides a controlled restriction to the main metering system. This solenoid responds to impulses (cycles) generated from the ECM to make the mixture leaner or richer, as determined by the system of engine sensors and switches.