What is the EGR valve for?
The
EGR valve is a mechanic car-part located in the engine compartment. Its function is to regulate the exhaust fumes of your car. Therefore its purpose is similar to that of the
catalytic converter.
In fact, the EGR valve (or exhaust gas recirculation) has been introduced in the 1970s in the US. Its purpose is to reduce NOx emissions by displacing combustible matter or lowering the temperatures in the combustion chamber, depending on the type of engine.
In a gasoline engine, an inert exhaust gas is added to the combustible matter. This gas slows down the combustion process. In a diesel engine the exhaust gas replaces part of the oxygen. As a result the temperatures in the combustion chamber decrease. As NOx forms predominantly when oxygen and nitrogen are subjected to high temperatures, the emission of this gas is reduced by lowering temperatures.
The
EGR valve is operated by a calculator. The
EGR itself then recirculates part of the engine’s exhaust gasses back to the engine.