What is the EGR Pressure Feedback Sensor all about?

Nearly all vehicles are equipped with an emissions-reducing system known commonly as EGR, which stands for exhaust gas recirculation. The premise of the system is that exhaust gases are re-introduced or recirculated into the intake manifold and burned alongside the air/fuel mixture. It performs a more complete burn on the exhaust gases, reducing temperatures inside the combustion chamber, which in turn reduces nitrous oxide production and emissions.

The EGR valve controls the amount of exhaust gases that flow into the intake manifold. One sensor that assists in the EGR valve’s control is the EGR pressure feedback sensor. Commonly known as delta pressure feedback EGR, or DPFE, the pressure feedback sensor measures the pressure at both the intake and exhaust ends of the EGR tube. These values are relayed to the powertrain control module. The powertrain control module then determines any changes to the EGR valve’s position. If the DPFE isn’t working, or is reading incorrect values, an incorrect amount of exhaust gas can enter the intake manifold, typically less exhaust gases than there should be. The results are engine knock, internal engine damage, an active Check Engine Light, and a vehicle incapable of passing a smog test.

Keep in mind:

• The exhaust system is very hot at operating temperature. Allow the engine and exhaust to cool down before attempting any servicing or inspection.
• The EGR pressure feedback sensor is an electrical component and is difficult to diagnose without specialized equipment. Have one of our expert technicians perform your diagnosis if you suspect an EGR pressure problem.

How it's done:

• The EGR pressure feedback sensor is verified that it needs to be replaced. The engine top trim panel is then removed for access.
• The defective EGR pressure feedback sensor is removed by disconnecting the clip and hose.
• The new EGR pressure feedback sensor is installed and the clip and hose are reconnected.
• The engine is started and the EGR pressure feedback sensor is tested for operation and old codes are cleared.
• The vehicle is road tested to ensure proper operation of the EGR pressure feedback sensor.

Our recommendation:

The EGR pressure feedback sensor is exposed to high temperatures, which makes it prone to premature failure. If one of our expert technicians diagnoses the EGR pressure feedback sensor and concludes that it is faulty, the sensor needs to be replaced. Have the EGR valve inspected at the same time.

What common symptoms indicate you may need to replace the EGR Pressure Feedback Sensor?

• Check Engine light is on
• Engine runs rough or knocks
• Failed smog test

How important is this service?

An uncorrected EGR problem can cause internal engine damage, a failed emissions test, and generate powertrain control module failure codes that will illuminate the Check Engine light. Replace the DPFE as soon as possible to prevent additional problems.