EGR Control Solenoid: Description and Operation

Civic VTEC-E 16 VALVE SOHC Engine Control Box:

PURPOSE

Regulates vacuum to the Exhaust Gas Recirculation (EGR) valve, controlled by the Engine Control Module (ECM).

OPERATION

The ECM contains memories for optimum EGR lift during various conditions. It reads actual EGR position from the Lift Sensor.
The sensor uses a plunger operated potentiometer supplying a signal to the ECM. If the EGR actual position differs from it's preferred position, the ECM cuts control solenoid power to reduce vacuum applied to the EGR valve.

CONSTRUCTION

The sensor uses a plunger operated electric solenoid, with a vacuum chamber mounted below to control engine vacuum.