Roadmaster Estate Wagon V8-350 5.7L (1993)
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EGR Electronic Vacuum Regulator Solenoid: Description and Operation
Wiring Diagram
The ECM operates a vacuum solenoid to control the EGR valve. The solenoid is normally closed. The ECM provides a ground path to energize the
solenoid. This allows vacuum to flow to the EGR valve.
The ECM control of the EGR valve is based on the following inputs;
^
Engine coolant temperature above 25°F
^
TPS off idle
^
MAP