P0475 Exhaust Pressure Sensor Intermittent

As a car owner, you might have heard of an exhaust pressure sensor before.

This small but essential component plays a vital role in the functioning of your vehicle’s engine and exhaust system.

If you’re experiencing issues with your car’s performance, it could be due to a faulty exhaust pressure sensor. In this article, we’ll discuss what an exhaust pressure sensor is, how it works, and how to diagnose and fix any problems related to it.

What is an Exhaust Pressure Sensor?

An exhaust pressure sensor, also known as an EGR (Exhaust Gas Recirculation) pressure sensor, is a device that monitors the pressure of the exhaust gas recirculation system in a vehicle.

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The EGR system is responsible for reducing harmful nitrogen oxide emissions by recirculating some of the exhaust gases back into the combustion chamber. The exhaust pressure sensor ensures that the system is working correctly by measuring the pressure of the exhaust gases.

How does an Exhaust Pressure Sensor work?

The exhaust pressure sensor works by measuring the pressure of the exhaust gases in the EGR system. It does this by using a diaphragm that reacts to pressure changes in the system.

The diaphragm is connected to a Wheatstone bridge circuit that converts the pressure changes into electrical signals. These signals are then sent to the engine control module (ECM) or powertrain control module (PCM), which uses the information to adjust the engine’s performance.

Symptoms of a Faulty Exhaust Pressure Sensor

If the exhaust pressure sensor is faulty, it can cause several issues with your vehicle’s performance. Some of the common symptoms of a faulty exhaust pressure sensor are:

  1. Check Engine Light: A faulty exhaust pressure sensor can trigger the check engine light to come on. The ECM or PCM will detect that the sensor is not functioning correctly and will illuminate the warning light.
  2. Poor Performance: A faulty exhaust pressure sensor can cause poor engine performance, including reduced power, acceleration, and fuel efficiency.
  3. Rough Idling: If the exhaust pressure sensor is malfunctioning, it can cause the engine to idle roughly or even stall.
  4. Emissions Problems: A faulty exhaust pressure sensor can cause increased emissions, which can lead to your vehicle failing emissions tests.

How to diagnose a Faulty Exhaust Pressure Sensor

If you’re experiencing any of the symptoms mentioned above and suspect that the exhaust pressure sensor is the culprit, you can diagnose the problem by following these steps:

  1. Check Engine Light: If the check engine light is on, you can use an OBD-II scanner to read the fault codes. A faulty exhaust pressure sensor will usually trigger a P0475 code.
  2. Visual Inspection: Inspect the sensor and wiring for any signs of damage or corrosion.
  3. Test the Sensor: You can test the sensor’s resistance using a multimeter. The resistance should vary as you apply pressure to the diaphragm.

How to fix a Faulty Exhaust Pressure Sensor

If you’ve diagnosed a faulty exhaust pressure sensor, you’ll need to replace it. Here’s how:

  1. Locate the Sensor: The exhaust pressure sensor is usually located near the EGR valve.
  2. Remove the Sensor: Disconnect the wiring and remove the sensor from its mounting.
  3. Install the New Sensor: Install the new sensor in place and reconnect the wiring.
  4. Clear the Codes: Clear any fault codes using an OBD-II scanner.

Conclusion

The exhaust pressure sensor is a crucial component of your vehicle’s EGR system. If it’s not working correctly, it can cause several performance issues and even lead to emissions problems. By understanding how the sensor works, how to diagnose and fix any issues, you can ensure that your vehicle runs smoothly and efficiently.

FAQs

  1. Can a faulty exhaust pressure sensor cause my car to fail emissions tests?

Yes, a faulty exhaust pressure sensor can cause increased emissions, which can lead to your vehicle failing emissions tests.

  1. How do I diagnose a faulty exhaust pressure sensor?

You can diagnose a faulty exhaust pressure sensor by checking the check engine light, performing a visual inspection, and testing the sensor’s resistance.

  1. Where is the exhaust pressure sensor located?

The exhaust pressure sensor is usually located near the EGR valve.

  1. Can I drive my car with a faulty exhaust pressure sensor?

It’s not recommended to drive your car with a faulty exhaust pressure sensor as it can cause poor engine performance and increased emissions.

  1. What is the purpose of the exhaust pressure sensor?

The exhaust pressure sensor measures the pressure of the exhaust gases in the EGR system and ensures that it’s functioning correctly.