What to know about the EGR Pressure Feedback Sensor:
Nearly all vehicles are furnished 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, bringing down temperatures inside the combustion chamber, which in turn reduces nitrous oxide production and emissions.
The EGR valve regulates the amount of exhaust gases that flow into the intake manifold. One sensor that aids in the EGR valve’s control is the EGR pressure feedback sensor. Usually 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 decides 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.
READ ALSO: HOW TO DO EGR COOLER REPLACEMENT
Facts to Note:
The exhaust system is very hot at working temperature. Allow the engine and exhaust to cool down before trying any servicing or inspection.
The EGR pressure feedback sensor is an electrical component and is difficult to analyse without specialized equipment. Have one of your expert technicians perform your analysis if you suspect an EGR pressure problem.
How to Fix:
The EGR pressure feedback sensor is confirmed that it needs to be changed. The engine top trim panel is then removed for access.
The faulty EGR pressure feedback sensor is detached by disconnecting the clip and hose.
The new EGR pressure feedback sensor is fixed 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.
The EGR pressure feedback sensor is exposed to high temperatures, which makes it prone to premature failure. If one of your expert technicians diagnoses the EGR pressure feedback sensor and concludes that it is faulty, the sensor needs to be changed. Have the EGR valve checked at the same time.
Common symptoms indicating you may need to change the EGR Pressure Feedback Sensor:
Check Engine light is on
Engine runs rough or knocks
Failed smog test
Importance of this service:
An uncorrected EGR issue can cause internal engine damage, a failed emissions test, and create power-train control module failure codes that will illuminate the Check Engine light. Replace the DPFE as soon as you can to prevent additional issues.