K 1500 Truck 4WD V6-262 4.3L VIN Z (1992)
EGR Control Solenoid: Description and Operation
Negative Backpressure EGR Control Solenoid
EGR System
OPERATION:
To regulate EGR flow an ECM controlled solenoid is used in the vacuum line. This is a normally closed solenoid vacuum valve which is opened
when the ECM completes the ground. The ECM will energize the EGR solenoid (EGR ON) when the engine is warm and above idle. There is
little EGR flow at wide open throttle due to lack of engine vacuum.
