How to test DPFE Sensor? | DPFE Sensor Symptoms, Causes

Modern vehicles are equipped with many advanced sensors designed to ensure optimum performance. One example is the Differential Pressure Feedback Electronic (DPFE) sensor. DPFE is part of the EGR system. The DPFE sensor is installed in many Ford and Lincoln engines and monitors the pressure in the EGR system. This article mainly explains the symptoms, function, and causes of a bad DPFE sensor.

What is a DPFE Sensor?

The DPFE sensor provides information to the Powertrain Control Module (PCM) to tell it how much exhaust gas is flowing through the EGR system. The PCM uses this information to control the EGR Valve, EGR sensor, and other factors to optimize engine performance and emissions.

DPFE Sensor

The powertrain control module also uses the DPFE sensor to monitor the flow rate of exhaust gases towards the intake manifold, which routes the gases into the cylinders.

The DPFE sensor helps reduce heat during the combustion process, which in turn prevents the formation of highly toxic oxides of nitrogen (NOx) and detonation.

If your vehicle is experiencing symptoms of a bad DPFE sensor, it can become difficult to drive and create an excessive amount of air pollution.

When the DPFE sensor fails, it leads to poor engine performance and reduced fuel economy. The Check Engine Light might also come on the dash, and your vehicle could fail an emissions test. However, replacing the DPFE sensor is a simple fix that should restore the car’s original performance.

Working of DPFE Sensor

The EGR system is the Exhaust Gas Recirculation system. It is the process used to suck exhaust gas back into the motor, so it can burn again. This modern technology helps to reduce pollutants coming from the vehicle.

Working of DPFE Sensor

The two tubes that attach to the DPFE sensor are pressurized when the gases come through the EGR tube. The DPFE sensor determines the difference in pressures between the two tubes to determine how much gas is flowing through the system. This information is then sent to the PCM so the actuator can be controlled better, allowing the proper amount of gas through.

Without the DPFE sensor, the wrong information is sent, leading to an imbalance of the exhaust gases. 

Bad DPFE Sensor Symptoms

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

  1. Poor engine performance
  2. Poor fuel economy
  3. Check engine light
  4. Failed emissions tests
  5. Rough idle
  6. Misfire

1) Poor Engine Performance

When the DPFE sensor fails, the engine can’t run as it was designed. In fact, engine performance issues are the first sign that something is wrong with this sensor. 

With a faulty sensor, the wrong information is sent back to the powertrain control module (PCM) computer, and because of this bad data, the EGR system malfunctions. With this system not running properly, you will notice reduced power and a rough idle.

2) Poor Fuel Economy

For your vehicle to receive the EPA-estimated fuel economy numbers, everything must be running perfectly in the engine. Poor fuel economy is one of the most common symptoms of a bad DPFE sensor.  

When the DPFE sensors go bad, they send wrong information to the ECU, and the motor is going to work harder to compensate for the faults. This extra effort requires more fuel, which is why you might start spending more time at the gas station. 

3) Check Engine Light

When the computer system recognizes a problem, the Check Engine Light comes on. In this case, the fault is related to a malfunctioning EGR pressure sensor signal. 

However, a Check Engine Light alone doesn’t indicate a faulty DPFE sensor. In fact, this light comes on whenever there is a problem with the motor. The only way to know for sure is with an OBDII code scanner. 

Read More: Causes of Check Engine Light Flashing 

4) Failed Emissions Tests

The DPFE sensor is required for a well-running EGR system. The vehicle will fail an emissions test when the EGR system isn’t running as it should.

Every state has laws about emissions tests, often required for registration. If your vehicle can’t pass the emissions test, you might have trouble driving legally, and you are contributing to more pollution in the environment.

5) Rough Idle

The bad DPFE sensors may go lead to rough idling. A rough idle when starting your vehicle or during brief stops (i.e., low engine speeds with a warmed-up engine) can be caused when the EGR is constantly open, and a continuous flow of exhaust gases goes into the intake manifold.

6) Misfire

As the DPFE goes bad, it increases the emission of exhaust gases. This excessive amount of EGR combined with the air coming in via the throttle body leans out the fuel mixture, causing a lean misfire, which is the “stumble” or “hesitation” that is common as the DPFE Sensor fails.

Read More: Causes and Symptoms of bad PCM

Causes of a bad DPEF Sensor

A DPEF sensor may go bad due to one of the below-given symptoms:

  1. Blocked EGR passages
  2. Damaged EGR valve
  3. Faulty vacuum hose
  4. Clogged intake and exhaust valves

How to diagnose a bad DPFE sensor?

Whenever you suspect a problem with the DPFE sensor, test it first. A bad signal from the sensor doesn’t necessarily mean a bad sensor. A faulty vacuum hose, a restriction in an EGR passage, or a faulty EGR valve can cause the DPFE sensor to report false information to the PCM.

Follow the below-given steps to test the bad DPFE sensor:

  1. Set the emergency brakes.
  2. Set the transmission to Park (automatic) or Neutral (manual).
  3. Pop the hood open.
  4. Locate the DPFE sensor in your vehicle. Look for an aluminum or plastic rectangle with an electrical connector and two vacuum hoses that plug into the EGR’s exhaust-to-intake pipe (see the photograph at the top of this post).
  5. Unplug the two vacuum hoses from the sensor.
  6. Turn the ignition key to the On position, but don’t start the engine.
  7. Set your DMM to the DC voltage scale, and select a low setting.
  8. Connect your DMM’s black lead to battery ground (the battery post marked with the minus “-” symbol).
  9. Turn on your DMM.
  10. Using your meter’s red lead, back probe the sensor’s signal wire. If you don’t know which wire this is, consult the electrical diagram in your vehicle repair manual.
  11. Depending on your particular model, the signal from the sensor may be around 0.55 volts (most Fords). The signal is proportional to intake manifold pressure.

DPFE Sensor Replacement Cost

The replacement and repair costs of a DPFE sensor vary according to the vehicle model and nature of the repair. The average replacement cost of a DPFE sensor and EGR valve is between $140 and $510. In this cost, the parts make up most of the cost, usually between $90 and $410, while the labor might only be $40 to $90. However, replacing the DPFE sensor is a simple task that can be done with a few everyday tools.

FAQ Section

What is EGR differential pressure?

The EGR differential pressure sensor measures the exhaust gas pressure drop across the EGR differential pressure orifice. This pressure drop is used to calculate the amount of EGR flow into the intake manifold.

What is the function of the DPFE Sensor?

The DPFE sensor stands for Differential Pressure Feedback of EGR. It’s also called the Delta Pressure Feedback of EGR because “Delta” means change. 

The DPFE sensor is a transducer that detects changes in pressure in the EGR system (to know exhaust gases are flowing) and sends this information in the form of a voltage signal to the PCM.

Using the voltage signal from the sensor, the PCM decides whether to open or close the EGR valve according to information it receives from other sensors.

What is a DPFE sensor Ford?

DPFE (Differential Pressure Feedback Electronic) sensor is an integral part of the EGR (Exhaust Gas Recirculation) System. The DPFE Sensor provides information to the Powertrain Control Module (PCM) to tell it how much exhaust gas is flowing through the system.

Where is DPFE Sensor Located

The DPFE sensor is usually located near the EGR valve. The EGR valve is found behind the upper intake manifold between the motor and the firewall.

The DPFE sensor is often shaped like a small square. You will see two vacuum hoses attached to the bottom, and there is a wiring harness coming from its side.

However, the exact location can vary based on what model vehicle you drive. Therefore, it’s best to consult your service manual for a diagram and the exact location. 

What happens when a DPFE sensor goes bad?

When the DPFE sensor fails, it leads to poor engine performance and reduced fuel economy. The Check Engine Light might also come on the dash, and your vehicle could fail an emissions test.

Can I drive with a bad DPFE Sensor?

You shouldn’t drive with a faulty DPFE sensor. If you are noticing a rough idle or a lack of engine power, it’s best to replace the DPFE sensor and EGR valve. Leaving the car with a faulty EGR system only causes trouble passing emissions tests.

Can a bad DPFE sensor cause a misfire?

The excessive amount of EGR combined with the air coming in via the throttle body leans out the fuel mixture, causing a lean misfire, which is the “stumble” or “hesitation” that is common as the DPFE Sensor fails.

What does DPFE stand for on a Ford?

DPFE stands for Differential Pressure Feedback Electronic. It isan integral part of the EGR (Exhaust Gas Recirculation) System.

How do you clear a DPF warning light?

When the DPF light has become illuminated, it tells you that ‘passive regeneration’ has failed and that you need to regenerate the diesel particulate filter actively. You can do this by increasing your speed to more than 40mph for between 10 and 15 minutes.

Can a blocked DPF damage the engine?

Blocked DPFs wreak havoc with the delicate balance of your engine by preventing the normal venting of gases, which reduces the engine performance and fuel economy. In addition to reduced power and fuel efficiency, a blocked filter may eventually cause a dangerous mechanical malfunction and break your engine.

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