Exhaust Gas RECIRCULATION (EGR) System: Description: Notes

The Exhaust Gas Recirculation (EGR) system is designed to lower burning temperatures of gases in combustion chambers, thereby reducing formation of oxides of nitrogen (NOx). Metered amounts of exhaust gas dilutes air/fuel mixture, lowering combustion temperatures. This system consists of a diaphragm-actuated EGR valve, coolant temperature override switch (CTO), a thermal vacuum switch (TVS) and connecting hoses.