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EGR Electronic Vacuum Regulator Solenoid: Description and Operation

ENGINE CONTROL COMPONENTS

Exhaust Gas Recirculation (EGR) Vacuum Regulator Solenoid
The EGR vacuum regulator solenoid is an electromagnetic device used to regulate the vacuum supply to the EGR valve. The solenoid contains a coil which magnetically controls the position of a disc to regulate the vacuum. As the duty cycle to the coil increases, the vacuum signal passed through the solenoid to the EGR valve also increases. Vacuum not directed to the EGR valve is vented through the solenoid vent to the atmosphere. At 0% duty cycle (no electrical signal applied), the EGR vacuum regulator solenoid allows some vacuum to pass, but not enough to open the EGR valve.