EGR Electronic Vacuum Regulator Solenoid: Description and Operation

EGR Vacuum Regulator (EVR) Solenoid:

CONSTRUCTION
The EGR Vacuum Regulator (EVR) is a single unit electromagnetic device with two vacuum ports.

PURPOSE
The EVR allows the Powertrain Control Module (PCM) to modulate the EGR valve opening to any degree, by controlling the ground circuit.

OPERATION
When the PCM grounds the EVR circuit, a magnetic field is produced from the energized coil. This magnetic field lifts the metal disk, opening the vacuum passages.

Engine vacuum is now applied to the EGR valve and the valve opens. The PCM cycles the EVR "ON" and "OFF" rapidly in order to control EGR valve opening and therefore exhaust gas recirculation flow.