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EGR valve, also called valve
EGR (Exhaust Gas Recirculation), is a device which allows part of the exhaust gas to be reintroduced into the engine.
It is mainly used in
diesel engines to improve their performance and reduce polluting emissions.
What is a heat engine?
A heat engine converts chemical energy from fuel combustion into mechanical energy. Internal combustion engines include
gasoline engines and diesel engines.
In a
diesel engine, fuel and air are mixed and delivered into a cylinder by a fuel injector.
fuel. The high pressure and temperature of the mixture causes it to burn, which drives the piston and turns the crankshaft.
Principle of operation of an EGR valve
In order to reduce pollutant emissions and improve overall engine efficiency, certain diesel engines are equipped with a
EGR system. As its name suggests, this technology consists of recirculating part of the exhaust gases towards the engine. This is done using a special valve that controls the gas flow. The valve can be operated by electrical or hydraulic control.
When the
EGR valve is opened, some of the cooled exhaust gas is drawn into the engine. These gases contain hydrocarbons and
carbon monoxide which will not be burned during the normal combustion cycle.
By returning these unburned combustion products back into the engine, the combustion process is improved and fuel consumption is reduced.
Benefits of the EGR valve
Improves performance - Adding exhaust gases to the air/fuel mixture increases the total amount of fuel available. Thus, more fuel is burned, increasing engine efficiency and reducing fuel consumption.
Reduces polluting emissions - Exhaust gases are not burned completely in the engine. As a result, fewer pollutants are released into the atmosphere. This means that the engine meets European emissions standards and is therefore more environmentally friendly.
How does the EGR valve control work?
Control of the
EGR valve is carried out by a valve position sensor. It sends information to the vehicle's electronic control unit, which controls the opening and closing of the
EGR valve. This allows the exhaust gas recirculation rate to be adapted depending on various factors, such as engine load and temperature.
The amount of recirculated exhaust gas is also controlled by injection and intake valves. These valves allow the air/fuel ratio to be adjusted for each cylinder to maintain the optimal mixture to reduce polluting emissions.
Maintenance of the EGR Valve
To ensure a good
functioning and a long lifespan,
EGR valve must be well maintained. Regular inspection is recommended to verify the good condition of the valve. In addition, it is important to have the
diesel particulate filter to prevent exhaust gases from accumulating in the
EGR system.
Another important maintenance measure is to regularly clean the
EGR valve to avoid the accumulation of carbon residues. This cleaning can be carried out using a special product or a
high pressure cleaner.
It is important to follow the manufacturer's instructions to ensure safe and proper cleaning.
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EGR valve plays an important role in the proper functioning of diesel engines. It helps reduce fuel consumption and polluting emissions by recycling exhaust gases.
Although this technology offers many advantages, it must be properly maintained to ensure proper engine operation. Good maintenance includes
regular inspection and cleaning of the valve.
