Mercedes-Benz ML400 EGR Pressure Feedback Sensor Replacement at your home or office.

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.