Pacbrake Blog

How Do You Identify Problems Associated With The EGR Valve?

July 12, 2014

The EGR, or Exhaust Gas Recirculation system, is one of the most important components in any automobile engine. Understanding how it works and making sure that yours is in good condition is therefore essential if you are interested in keeping your truck running efficiently. Most of the modern truck engines made in the past two decades or so have an EGR valve fitted. This means that the only way you can be sure that your truck engine does not have one is if it’s a very old truck.


What is the role of the EGR valve?

In a nutshell, the EGR is there to reduce emissions. It does this by rerouting some of the exhaust gases coming from the engine back into the combustion chambers in the engine. This has the effect of reducing the temperatures within the combustion chambers.

When the air/fuel mixture in an engine is burnt at a very high temperature, greenhouse gases such as nitrous oxide tend to be produced. By reducing the combustion temperatures through the use of the EGR valve, this is reduced dramatically without having a significant impact on the efficiency of the truck. In the end, the presence of the EGR makes your truck more environmentally friendly.

Making sure that the valve is in optimal condition is essential to the truck’s function

As a truck owner, it’s important that you keep the EGR valve in good condition. Since it has a direct impact on how the engine works, any problem with the EGR will manifest either as increased fuel consumption or reduced performance. Learning when to have it maintained or replaced is therefore important. Some of the signs that could point to a faulty EGR include:

• An EGR valve that is stuck open: if your truck has a mechanical EGR valve and it happens to be stuck open, it will act as a conduit which causes a vacuum leak in the engine. Some of the manifestations of this include rough idling and even a feeling of hesitation when you try to accelerate. When the problem is severe, you will also notice the truck stalling frequently. When the EGR valve is stuck open, it means that all the exhaust will be rerouted to the combustion chamber, which means that there will be little oxygen which is what is needed for the combustion.

• A valve that is stuck closed: on the opposite end of the spectrum, you can also have a valve that is shut and won’t open. In such cases, there will be an increase in the quantity of nitrous oxide gas in the cylinders, and this will manifest as the engine knocking.

These are the two common problems that afflict the mechanical EGR valves, and thankfully they are easy to fix. All you need to do is identify a competent garage, and have them fix it for you. If you are handy with your tools, you can even maintain and replace the EGR valve with ease. Of course, to do the latter, you will need to buy high quality spare parts from the right sources.