EGR Electronic Vacuum Regulator Solenoid: Description and Operation

EGR Vacuum Regulator:

The EVR applies, traps, or bleeds off vacuum to the EGR valve. The EVR is an electromagnetic device which uses an electric current to induce a magnetic field in the armature. The magnetic field pulls the disk closed, closing the vent and increasing the vacuum level. As the duty cycle is increased, an increased vacuum signal is sent to the EGR valve. When a steady source of vacuum is needed to maintain EGR position, the EGR traps the vacuum in the tubing until a signal from the EEC indicates a change in driving conditions and then increases or decreases vacuum to the EGR valve. To bleed or cut off vacuum to the EGR valve, the EVR is de-energized allowing vacuum to vent off to atmosphere.