Exhaust Gas Recirculation (EGR) Control

Fig. 101 EGR Control System:

CIRCUIT OPERATION
The EGR control system is used to allow precise control of the EGR valve.
When conditions are NOT suitable for EGR operation, based on signals sent via the crank angle sensor, air flow meter, engine temperature sensor and the vehicle speed sensor, the ECU energizes the solenoid. Refer to EMISSION CONTROLS for further description of the EGR valve.

Fig. 142 Vacuum Control Solenoid:

EGR CONTROL SOLENOID
The ECU supplies the ground circuit to the solenoid. This energizes the solenoid, redirecting vacuum from the source port and valve port to the source port and vent port preventing EGR operation.

Fig. 149 EGR Operation:

Refer to the chart for conditions necessary for EGR operation.