EGRsysteem

EGR stands for Exhaust Gas Recirculation. An EGR system is a pollution control technology that reduces nitrogen oxide (NOx) emissions in internal combustion engines. NOx is a harmful pollutant that contributes to smog and acid rain. The EGR system works by recirculating a small portion of the exhaust gas back into the engine's intake manifold. This exhaust gas mixes with the incoming air-fuel mixture, lowering the combustion temperature. Lower combustion temperatures significantly reduce the formation of NOx.

The EGR system typically consists of an EGR valve, an EGR cooler, and associated plumbing. The EGR valve is a crucial component that controls the amount of exhaust gas being recirculated. It can be vacuum-actuated or electronically controlled. In some systems, an EGR cooler is used to further reduce the temperature of the exhaust gas before it enters the intake manifold, which can improve efficiency and further reduce NOx emissions.

When the engine is under light load or at idle, the EGR valve is usually closed, preventing exhaust gas from entering the intake. This is because recirculating exhaust at these conditions can lead to rough idling and poor performance. However, under moderate to heavy loads, when combustion temperatures are higher, the EGR valve opens to allow a controlled amount of exhaust gas to be recirculated. The precise operation and calibration of the EGR system are managed by the engine's control unit (ECU). Over time, EGR systems can become clogged with carbon deposits, which can impair their function and lead to increased emissions or performance issues, often requiring cleaning or replacement of components.