Exhaust Gas Recirculation: Description and Operation
EGR System Diagram:
PURPOSE
System lowers combustion chamber temperatures to reduce NOx emissions.
LOCATION
^ EGR valve: end of intake manifold
^ EGR vacuum and vent solenoids: bracket on intake manifold.
^ EGR function sensor: on EGR valve.
OPERATION
System recirculates a portion of exhaust gas through the EGR valve and intake manifold into the combustion chambers. Valve operation is PCME controlled with the vacuum and vent solenoid valves. To improve driveability when engine is cold, system does not operate when coolant temperature is below 131°F (55°C).
At operating temperature, system functions as described on image chart:
EGR System Operating Conditions:
