Exhaust Gas Recirculation & Canister Purge Control

Exhaust Gas Recirculation (EGR) System Inputs And Outputs:

CIRCUIT OPERATION
The EGR and Evaporative Canister control system is used to allow precise control of the EGR and Canister valves. The 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:

EGR/CANISTER 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 or Canister Purge.

If the ECM senses any condition other than above, the EGR/Canister Solenoid will be de-energized and allow vacuum to pass.

Refer to EMISSION CONTROLS for further description of the EGR system.