EGR Valve: Description and Operation

PURPOSE

The Exhaust Gas Recirculation (EGR) valve is the controlled port through which the exhaust gases enter the intake manifold.

OPERATION

Vacuum to the EGR Valve is controlled by the Engine Control Module (ECM) and monitored by the EGR Valve Lift Sensor. Vacuum applied to the top of the valve causes the internal diaphragm to lift the pintle from it's seat, allowing exhaust gases to pass through the opening.