Exhaust Gas Recirculation: Description and Operation

Exhaust Gas Recirculation Control System:

PURPOSE
The EGR System lowers combustion chamber temperatures to reduce NOx emissions.

OPERATION
The EGR system recirculates a portion of exhaust gas through the EGR valve and intake manifold into the combustion chambers. EGR valve operation is powertrain control module engine (PCME) controlled via vacuum and vent solenoid valves. The EGR system does not operate when coolant temperature is below 55°C (131°F), to improve driveability when engine is cold.

EGR System Operating Conditions:

At operating temperature, the system functions as described on image chart.