Vacuum Control Solenoid Valve Operation

EGR System Vacuum Connections:

Electric EGR Transducer (EET):

NOTE: The EET assembly is a vacuum control solenoid and a backpressure transducer, in one package.

PURPOSE

The PCM controls when the EGR valve can be actuated, through the solenoid portion of the EET.

OPERATION

Ported vacuum from the throttle body, is supplied to the solenoid valve.

The PCM controls the flow of vacuum between the throttle body and the back pressure transducer, (through the solenoid valve ground circuit).

- When the solenoid is energized (grounded), no vacuum is supplied to the transducer.

- When the solenoid is de-energized (not grounded), vacuum is supplied to the transducer.

The solenoid will always be energized (no EGR), under following conditions:

- Engine warm-up, (engine coolant temperature below 40 ~F)
- Engine at idle
- Wide Open Throttle (WOT) operation
- Rapid acceleration/deceleration
- During EGR system diagnostic check

NOTE: If the wiring or connector is disconnected from the solenoid, the EGR valve will operate at all times, (adversely affecting engine idle and performance).