How does a DPFE Sensor work? | DPFE Sensor Function, Symptoms

The latest vehicles have multiple devices with highly proficient sensors that sense the data efficiently and forward it to the PCM. Differential Pressure Feedback Electronic (DPFE) sensor is a major sensor of the vehicle. Basically, it is an integral part of the EGR system of your vehicle. The primary function of the DPFE sensor is to measure air pressure in the EGR system. DPFE sensor is most commonly used in Lincoln and Ford engines.

In this article, you will mainly learn about the bad DPFE sensor symptoms, causes, function, and replacement cost.

What is a DPFE Sensor?

A DPFE sensor is a vehicle sensor that senses the gas pressure passing through the EGR system of the vehicle and transfers this information to the PCM. The Powertrain Control Module (PCM) utilizes this data to control the EGR sensor, the EGR valve, and some other functions to maximize the engine performance and minimize the emission rate.

DPFE Sensor

The PCM monitors the flow of unwanted gases to the intake manifold and directs the flow towards the cylinders using the DPFE sensors. These sensors assist in minimizing the heat created in the combustion process and hence restrict the production of NOx, which is very toxic and bad for the environment.

With the fault in the DPFE sensor, you will find it hard even to drive your car, and your vehicle will produce extreme exhaust gases that will be a reason for environmental pollution.

Similarly, failure in the sensor leads your car to the worst engine performance and unusual fuel consumption. In such a condition, your car PCM will turn on the check engine light on your vehicle’s dashboard, and your vehicle will not pass the emission test. So, the solution to all these troubles is to replace the DPFE sensor to take your vehicle back to the road with confidence.

Working of DPFE Sensor

The Exhaust Gas Recirculation system is one of the most important parts of the car. Your vehicle’s EGR system pulls the exhaust gas and pushes it into the motor to burn it once again. This method is used to reduce the pollution from the unwanted exhaust gas that is thrown out of the exhaust system into the surroundings.

Working of DPFE Sensor

There are two tubes connected to the DPFE sensor. As the exhaust gases enter the EGR tubes, the tubes connected to the DPFE sensor are pressurized. The sensor uses the difference in the flow of pressure among these tubes to tell the exact gas pressure of the system.

After measuring the pressure difference, the sensor transfers information to the ECM. The ECM utilizes information to control the actuator, which allows the optimal amount of gas to pass.

Likewise, as the sensor goes bad, it doesn’t send the correct information to the ECM. As a result, the ECM doesn’t properly maintain the proper flow of exhaust gases, which may increase the emission of the exhaust gases.

Symptoms of bad DPFE Sensor

As the DPFE sensor goes bad, it gives one of the below-given symptoms:

  1. Excessive fuel consumption
  2. Check engine light
  3. Bad engine performance
  4. Failed emission test
  5. Misfire
  6. Rough idling

1) Excessive Fuel Consumption

If your automobile consumes more fuel than usual, it is likely that your vehicle has a faulty DPFE sensor. In other words, poor fuel economy can be a clear symptom of bad DPFE sensors.

Poor fuel economy

As the deferential pressure feedback electronic sensor goes bad, it doesn’t properly calculate the pressure of the EGR system and sends wrong information to the PCM. When PCM gets wrong information, the engine needs to work harder to balance the problems due to that it consumes more fuel than usual.

2) Check Engine Light

The check engine light is one of the first symptoms of a bad DPFE sensor. As this sensor goes bad, the vehicle computer sends a signal to the check engine light, which starts illuminating.

check engine light

The check engine light may illuminate due to various issues in your vehicle. For example, issues with wiring, a faulty PCM, etc. The best technique to determine whether or not the DPFE sensor is faulty is to use an OBD2 scanner to scan the trouble codes and identify the issues.

Read More: Causes of Check Engine Light Flashing 

3) Bad Engine Performance

The bad DPFE sensors may also lead to poor engine performance. 

Engine Performance reduction due to bad DPFE Sensor

As the DPFE sensor goes bad, it sends incorrect data to the PCM. Due to the wrong data, the PCM doesn’t efficiently regulate the functions of the engine. This incorrect data results in various imbalanced gas conditions in the EGR system. As a result, the engine’s power decreases, and you experience bad engine performance.

4) Failed Emission Test

Any problem with your car’s EGR system may result in excessive emissions. This excessive emission will result in a failed emission test for your vehicle.

Emissions Test failure due to bad Engine Performance reduction due to bad DPFE Sensor

On a humanitarian level, the bad DPFE sensors increase air pollution, which is destructive to all living things on our earth.

5) Misfire

Exhaust emissions increase when DPFE is damaged. This excess exhaust gas combined with air entering through the throttle body causes the fuel mixture to be lean, resulting in a lean misfire, “trigger,” or “hesitation,” which is common when the DPFE sensor fails.

Engine Misfiring due to bad Differential Pressure Feedback Electronic sensor

6) Rough Idling

The rough idling might also be caused by defective DPFE sensors. If EGR is on continuously and exhaust gases continue to go into the intake manifold, rough idling may occur when the vehicle is started or during engine warm-up.

Rough Idle

Read More: Symptoms and Causes of P0505

What are the causes of a bad DPFE Sensor?

The following are the major causes that may lead to a bad DPFE sensor:

  • Blockage in EGR passages
  • Clogged intake and exhaust valves
  • A faulty EGR valve
  • Damaged vacuum hose

How to test a bad DPFE Sensor?

Whenever you detect a bad differential pressure feedback electronic sensor, you must immediately test it. This is because incorrect sensor readings might be caused by a broken vacuum hose, a malfunctioning EGR valve, or an obstruction in the EGR path.

Follow these steps in order to test the DPFE sensor of your vehicle:

  • Put on the emergency brakes.
  • Set the transmission as neutral or park.
  • Lift the hood of your car.
  • Find the DPFE sensor. It is like a plastic or metallic rectangle with wire connections and two vacuum hoses.
  • Unplug the vacuum hoses.
  • Turn the ignition “On,” but do not start the engine.
  • Set the DMM to DC voltage, preferably on the low side.
  • Connect the black lead of the DMM to the battery ground and turn on the DMM.
  • Connect the back probe of the sensor’s signal wire to the red probe of the DMM.
  • The signal reading from the sensor should be close to 0.55V. This depends on the model of your vehicle, and these readings are proportional to the intake manifold.

Replacement Cost of DPFE Sensor

The replacement cost of the DPFE sensor varies according to the vehicle model, labor cost, and brand type.

The replacement cost of the DPFE sensor can be anywhere from $145 to $500. The cost of the parts themselves may be between $110 and $400, and the labor cost is between $35 and $100. The replacement of the Differential Pressure Feedback Electronic sensor is very simple and can be done with the help of some common tools.

Parts Replacement Cost$110 to $400
Labor Cost$35 to $100

FAQ Section

What is the function of the DPFE sensor?

The DPFE sensor stands for Differential Pressure Feedback of EGR. The main function of the DPFE sensor is to detect the pressure changes in the EGR system and forward the readings in the form of signals to the powertrain control module. Based on the readings, PCM controls the opening and closing of the EGR valve.

Where to find the DPFE Sensor in my vehicle?

Normally, the DPFE sensor is installed near the EGR valve. The EGR valve itself is located behind the intake manifold.

A DPFE sensor is a rectangular metallic or plastic box with two vacuum hoses and wires coming out of it. The exact location of the DPFE sensor depends on the model of the vehicle. It is always recommended to consult the manual to find the exact location of the sensor according to your vehicle model.

What happens if a DPFE sensor fails?

When the DPFE sensor goes bad, the engine performs poorly and consumes more gasoline than usual. Your vehicle check engine light may also illuminate, and your car may fail an emissions test. Replacing the sensor, on the other hand, is a straightforward remedy that should return the automobile to its former performance.

Can a blocked diesel particulate filter damage the engine?

When the diesel particulate filter (DPF) is clogged, the gases cannot be discharged normally, the engine’s delicate balance is seriously disturbed, and engine performance and fuel consumption decrease.

A clogged filter reduces power output and fuel efficiency and can ultimately lead to dangerous mechanical failure and engine damage.

Can I drive with a faulty DPFE Sensor?

No, you should not drive with a faulty DPFE sensor. It is better to replace the sensor and EGR valve if you notice a rough idle or a loss of engine power. Defective DPFE sensors will only complicate the passing emission test.

How do you clear a DPF warning light?

As the DPF light comes on, it indicates that the ‘passive regeneration’ has gone bad, and the diesel particulate filter needs to be actively regenerated. To do this, accelerate to over 40 mph in 9 to 16 minutes.

Read More
  1. Working of EGR System
  2. Symptoms and Causes of bad EGR Symptoms
  3. How to Clean EGR Valve
  4. Working of Engine Valve

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