Operation CHARM: Car repair manuals for everyone.
Hosted by mcallihan.com

Exhaust Gas Recirculation (EGR) Control System




DESCRIPTION
This system recirculates a small amount of exhaust gas into the intake manifold to reduce the combustion temperature, and reduce the NOx emissions.
This system consists of the EGR valve, EGR valve position sensor, two solenoid valves, powertrain control module (ECM) and input devices.

Operation
Cold Engine (Coolant temperature less than 55°C (131°F))
EGR operation is stopped to improve driveability when the engine temperature is cold.




Warm Engine
The powertrain control module controls the solenoid valves (vacuum side and vent side) to supply EGR gases as described in the image.