Few people know, but thanks to exhaust gas recirculation, it is possible to significantly reduce the fuel consumption of a car, increase engine performance, normalize its operation and reduce the level of detonation. There is such a system for a long time, and at the moment it is used on absolutely all vehicles. Even in the domestic "Niva" there is such a device.
What is this system for?
Exhaust gas recirculation is necessary so that the engine does not lose its power when emitting unburned fuel residues. And this happens as follows. With increasing temperature in the combustion chamber, nitrogen and oxygen begin to form nitrogen oxides. In a gasoline engine, O2 is needed for efficient combustion of fuel, and since nitrogen reduces its amount, the liquid does not completely burn out. As a result of this, gasoline simply flies into the pipe, fuel consumption increases, and the performance of the internal combustion engine decreases. The exhaust gas recirculation valve allows the fuel to burn out to the end, as a result of which the power and fuel consumption in the car are normalized.
What is this valve?
In appearance it is a small disk with a tube that connects to the intake manifold and is mounted on the cylinder head. In a calm state, the exhaust gas recirculation valve (including Audi) is closed. But as soon as the fuel is supplied to the engine, it is activated. The air pressure formed in the manifold forces the membrane to move, and it, in turn, opens the exhaust gas recirculation valve.
Varieties
There are currently several types of device data. The exhaust gas recirculation valve is mechanical (in turn, is divided into 5 modifications) and electronic (there are 3 modifications).
What is he doing?
This mechanism is a key component of the recirculation system. He returns back part of the burnt substances to the intake manifold and mixes them with air. The latter, in turn, increases the temperature of combustion (due to oxygen - O2). Thus, due to the artificial reduction of its content in the composition of the fuel-air mixture, a decrease in the degree of combustion occurs. In this case, oxygen interacts with nitrogen, and since the degree of temperature decreases, it becomes more, so gasoline burns completely in the chamber.
In addition, the exhaust gas recirculation valve (BMW including) significantly reduces pumping losses, since there is no such a large pressure drop across the throttle. A low combustion temperature reduces the level of detonation, and this is a big plus for the motor (there is no loss of torque). As for diesel engines, here the exhaust gas recirculation valve normalizes the “hard” engine idling: due to the reduced combustion temperature, the pressure in the chamber decreases, so there are no strong vibrations.