EGR Electronic Vacuum Regulator Solenoid: Description and Operation

EGR Valve Control Schematic:

EGR Valve Assembly Sectional View:

Powertrain Control Module (PCM) Wiring:

DESCRIPTION
The EGR valve regulates the amount of exhaust gas fed to the engine and is part of the Emission System. The PCM controls the EGR valve by sending a Pulse Width Modulated (PWM) signal to the bobbin and coil subassembly contained within the EGR valve. The PCM monitors various sensors to control the amount of EGR flow.


CIRCUIT OPERATION
The PCM commands the EGR valve to open a specific amount by varying the PWM signal to the linear EGR valve. The EGR contains a sensor that relates the actual valve position back to the PCM. Similar to Throttle Position sensor reading, the EGR pintle position is expressed as being 0% at closed postion and 100% at the fully open position. In this way, the PCM is constantly comparing commanded EGR position versus actual EGR position. This results in improved flow accuracy.



PCM CONTROL
The PCM controlled EGR Valve regulates the amount of exhaust gas fed to the engine. This device offers more precise EGR flow metering than a back pressure or digital type valve and superior emission control and driveability.

The PCM monitors the following sensors to control the linear EGR valve:
- Coolant Temperature (CT) Sensor
- Throttle Position (TP) Sensor
- Manifold Pressure (MAP)
- Manifold Air Temperature (MAT)
- Throttle Switch (ISC)
- RPM data
- Vehicle Speed Sensor (VSS)

LOCATION
The EGR valve is located on the top LH side of engine.