Exhaust Gas Recirculation: Description and Operation

EGR Circuit:

PURPOSE
The Exhaust Gas Recirculation (EGR) System controls the formation of Oxides of Nitrogen (NOx) Emissions by recirculating the exhaust gases into the combustion chamber to lower combustion chamber temperatures. This is done through the intake manifold.

DESCRIPTION
The system consists of the EGR Valve, Back-Pressure Transducer and a vacuum switching valve (VSV) Solenoid.

OPERATION
The EGR is controlled by the Engine Control Module (ECM) through an EGR vacuum switch valve (VSV) and Back Pressure Transducer (BPT). Vacuum is allowed to the EGR Valve at acceleration and shut "OFF" upon deceleration.