Know When it is Time to Replace Your EGR Valve

EGR is the Exhaust Gas Recirculation unit which does the job of keeping the pollutants under control in the exhaust system. Some vehicles have an internal EGR system and therefore does not have an external EGR valve. Those with an external EGR might get stuffed up and need to be cleaned or eventually replaced.

What is EGR?

As the name implies, the exhaust gases are sent back into the exhaust system and reused. This reduces the release of pollutants. In earlier times, the EGR system posed the threat of reduced fuel economy. With the development of automobile technology, the EGR system has been improvised to be extremely efficient.

Nitrogen oxide gas is the most harmful pollutant released by the car especially in diesel cars. Due to this restrictive behavior of the valve, there is a high chance of particles getting clogged in the valve or even a leakage.

What Happens When the EGR Valve is Faulty?

EGR system may become faulty because of issues in the wiring or the pneumatics. But most commonly the problem is due to the valve. Carbon deposits and soot can get clogged in the valve. It can be easily identified using a multimeter. But, it can detect the condition only upon total failure. It is, therefore, necessary to keep a watch for EGR valve failure symptoms.

With a faulty EGR valve, especially a leakage, there is the issue of leakage of pollutants which is released into the atmosphere. It reduces the efficiency of the vehicle.

EGR Valve Failure Symptoms

The EGR valve can be open or close. When the valve is open, the exhaust gases will flow back into the manifold. When the valve is closed, the exhaust gases will get blocked at the manifold. The related symptoms will help to recognize the valve failure.

1.    Vehicle Engine Performance

There will be a time lag when starting a cold engine or when the engine is warmed up, like a traffic signal. This is due to reduced power and acceleration. The engine tends to stall when it is idle.

The high temperature caused due to a closed valve can lead to knocking. It can also be identified with engine smoothness issues and overall performance.

2.    Fuel Odor

With a leaking EGR valve, hydrocarbons are released and this can be identified with the odor.

3.    Emission Test

Emission test is done at low RPM. When the EGR valve is faulty, the temperature in the fuel chamber is less and therefore the fuel does not burn completely. The unburned hydrocarbons thus released can be identified with the emission test.

4.    Check Engine Light

The vehicle can be plugged into the diagnostic system to know the fault. But most of the time, the Check Engine Light on the dashboard will come on. The internal diagnostic system does this job to warn the driver. There are several reasons why the check engine light goes on. Plugging the vehicle for exact error code can have the car scanned for EGR valve issue.

The EGR valve may need to be replaced or cleaned to remove the fault. This will depend on the level of damage and the model of the EGR valve. Early recognition can save you a few pennies before major damage is done to the valve.