EGR Control Solenoid: Description and Operation

Fig. 145 Vacuum Solenoid:

PURPOSE
The EGR Control Solenoid will either allow vacuum to pass to the EGR Valve or vent the vacuum based on signals from the ECM.

LOCATION
On the Intake Manifold, near the EGR Valve.

OPERATION
If the ECM senses:
^ Low engine coolant temperature
^ Engine cranking
^ Engine speed over 2700 rpm
^ Engine idling
^ Excessively high coolant temperature
it energizes the EGR Control Solenoid. An energized solenoid will vent the vacuum signal and NOT allow EGR operation.

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