Emission Control Components Description

Exhaust Gas Recirculation (EGR) System Inputs And Outputs:

CIRCUIT OPERATION
The Exhaust Gas Recirculation (EGR) and Evaporative Canister control system allows precise control of the EGR and Canister valves. The Engine Control Module (ECM) receives signals from the crank angle sensor, air flow meter, engine temperature sensor and the ignition switch to determine if operation is warranted. The ECM supplies the ground circuit for the solenoid.

Vacuum Control Solenoid:

If the ECM senses:
^ Low engine coolant temperature
^ Engine cranking
^ High speed engine operation
^ Engine idling
^ Excessively high coolant temperature
it energizes the EGR/Canister Control Solenoid. An energized solenoid will vent the vacuum signal and NOT allow EGR operation or Canister Purge.