If your Audi vehicle is knocking and has failed its emission test, there could be a problem on your EGR valve. Many say that there is something about an Audi vehicle, but if the Audi EGR is not working the way it should be working, then something might not be so good. EGR valve is one of the integral parts of the Audi vehicle emission and ignition systems. There are two common signs if you need to replace your vehicle's EGR valve: engine pinging or knocking and increased tailpipe emissions. And, these signs can give a negative impact on your vehicle's fuel efficiency and high performance.

EGR (Exhaust Gas Recirculation) Valve is responsible for controlling the Acura engine emission of the nitrous oxides through reduction of the combustion temperature. Also called as laughing gas, the nitrous oxide is formed when the fuel burns up to over 2,500 degrees F. With such combustion temperature, the nitrogen in the air mixes with the other by product gases that form this gas that is capable of altering one's person's bone marrow structure in about 3 to 4 hours exposure to it. When this gas is released to the atmosphere, it reacts with the oxygen and it becomes nitrogen dioxide. When the latter comes in contact with the hydrocarbons, it becomes smog, which is a pollutant.

The Audi EGR valve is a reduction technique that works by re-circulating the engine's exhaust gas back to the engine cylinders. Mixing the incoming air with the exhaust gases that were re-circulated dilutes the mix together with the inert gas, thus lowers the peak combustion temperatures. This is because the nitrogen oxide formation progress much faster on high temperatures, EGR valve serves to limit the generation of the nitrogen oxide. This nitrogen oxide is usually formed when a mix of nitrogen and oxygen is subjected to a high temperature.

EGR system does not usually require a regular maintenance, but then it should nevertheless be checked to be able to make sure you are always complying with the emission standards. However, a malfunctioning EGR valve can cause damage to your engine if it is not repaired right away.

So if you want don't want your Audi vehicle to fail the emission test and to avoid it from knocking, you should have a functioning EGR valve. And if you are also concern about the environment around you, it is right to have a functioning EGR valve. If you are looking for a replacement or a new EGR valve for your Audi vehicle, here in Parts Train all you have to do is simply browse through our catalog and choose the one that is right for your vehicle.