EGR System - Gasoline: Description

The exhaust gas recirculation (EGR) system is used to reduce the formation of NOx emissions by reducing combustion temperature. This is accomplished by recycling metered amounts of exhaust gas back into the intake system.

Each system has a vacuum operated EGR valve, vacuum modulator (VM), vacuum switching valve (VSV), bi-metallic vacuum switching valve (BVSV) and a vacuum transmitting valve (VTV). A thermostatic vacuum switching valve (TVSV) is used on some models to control EGR operation.