Differential Pressure Feedback EGR Sensor
- Check DPFEGR Output -
Connect scan tool to DLC. Start engine and run until operating temperature is reached. Using scan tool, access DPFEGR PID and record value under following parameters:
- KOEO, voltage specification is 0.2-1.3 volts.
- Hot idle, voltage specification is 0.2-1.3 volts.
- Driving at 30 MPH, voltage specification is 0.2-4.5 volts.
- Driving at 55 MPH, voltage specification is 0.2-4.5 volts.
If all voltage readings are within specification, Differential Pressure Feedback EGR (DPFEGR) sensor is okay. If voltage readings are not within specification, go to next step.
- Check DPFEGR Sensor Output By Applying Vacuum With Hand Pump -
Disconnect pressure hoses at DPFEGR sensor. Connect a hand vacuum pump to downstream connection at DPFEGR sensor (intake manifold side of sensor, or smaller diameter pickup tube). With KOEO, access DPFEGR PID. Apply vacuum to DPFEGR sensor and hold for a few seconds. Quickly release vacuum. Observe DPFEGR PID voltage:
- DPFEGR PID voltage must be 0.2-1.3 volts with ignition on and no vacuum applied.
- DPFEGR PID voltage must increase to more than 4 volts with vacuum applied.
- DPFEGR PID must drop to less than 1.5 volts in less than 3 seconds when vacuum is released.
Turn ignition off. If DPFEGR PID voltage indicates a fault in DPFEGR sensor, replace faulty DPFEGR sensor. If DPFEGR PID voltage does not indicate a fault in DPFEGR sensor, DPFEGR sensor is okay. Check for kinks, clogging or restriction in vacuum line to intake manifold.