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