EGR Control Solenoid: Description and Operation

EGR Solenoid Circuit:

PURPOSE
To regulate EGR flow by controlling the vacuum source to the EGR valve.

OPERATION
The ECM turns the solenoid "ON" to allow vacuum to the EGR valve The Coolant Temperature Sensor (CTS), Throttle Position Sensor (TPS), and Park/Neutral Switch transmit signals to the ECM in order to regulate the EGR solenoid. During cold and idle operations, the solenoid circuit is not grounded by the ECM, which does not allow vacuum to flow to the EGR valve.