Feedback Control Solenoid: Description and Operation

4-151 Engine
This solenoid is an electro-mechanical device integral with the E2SE carburetor that regulates the air/fuel mixture according to signals received from the MCU.
One terminal of the MC solenoid is connected to the MCU and the other is connected to a 12 volt power supply. The MCU functions as a switch that provides either a ground circuit for current flow to energize the MC solenoid or an open circuit to de-energize the MC solenoid. The MCU switches the MC solenoid 10 times per second.