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What is an EGR Sensor?

The exhaust gas recirculation (EGR) system works to lower temperatures and reduce nitrogen oxide emissions. The gas emissions will form when the temperature reaches about 2500 degrees Fahrenheit. The EGR sensor main work is to get small amounts of exhaust fumes back to decrease the temperature and ultimately decrease combustion.


The EGR is also giving pressure feedback that tells of any changes within the system. The sensor and the EGR valve works hand in hand to regulate the pressure such that when the pressure is low, the EGR valve will increase the flow and vice versa.

The moment an EGR system encounters some problems, the issues may spill over to the entire system leading to engine failures and performance issues. Some obvious issues such as increased emissions should alert you that something is not right with your engine’s sensor.

Issues Related to EGR Sensor

Engine Poor Performance

In many cases, you will encounter engine problems as the initial symptom of the sensor. If your sensor gives false readings, look out for symptoms like rough idle, decreasing engine power, fuel efficiency, and engine hesitation.

Failing Emission Tests

A failing emission test is a sign that your EGR sensor is failing. If the pressure inside the sensor changes the functionality of the system, your vehicle will give a failed emissions test.

In some states and countries, vehicles have to pass emission tests for them to be registered.

The Car’s Engine Light Comes on

Any sign that the EGR sensor has a problem is when the car engine light is permanently on. However, many other issues can bring about the check engine light, so it is essential to check if indeed the EGR sensor is sending some troubled codes.

The above conditions may as well explain why the EGR needs replacement before the engines to come to a standstill.

Fuel Odor

Because of the increased consumption of fuel, many hydrocarbons are going to form part of the exhaust emissions, thus intensifying fuel odor that can pass through the cabin as well.

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What to Do When Replacing the EGR Sensor

Sometimes y9ou do not need too much information on how to replace a car component especially when you have been observing your mechanic do it. Here are some of the tools that you will need:

  • The EGR valve
  • Gloves
  • Socket set and ratchet
  • Diagnostic tool
  • Wrenches

What to Do

  • Put the car in park and engage the emergency brakes. Use the car’s owner manual if you are unable to locate the EGR valve
  • Turn off the engine and disconnect the battery
  • Inspect all vacuum for any tears, rips, and holes and do the necessary replacements
  • Remove the vacuum lines from the EGR valve
  • Remove the bolts holding the EGR valve to the cylinder head
  • Remove the EGR valve as you pay close attention not to let in debris inside the open cylinder
  • Secure the new EGR valve and attach the vacuum lines
  • Reconnect the battery
  • Start the car and use the diagnostic tool to read any codes. Reset the error codes as you check the engine light
  • Do a test drive to ensure that the engine is running and idling smoothly.

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Final Word

The EGR sensor is one of the most critical components in your vehicle. The signal it sends are warnings that something needs to be addressed. The best place to have it checked or replaced is to take the car to a qualified mechanic who will help solve the issues presented by EGR codes.

The time it takes to replace your EGR sensor should not run into more than one hour including testing.

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