What is the working principle of the EGR valve on a car?
2 Answers
Working principle of the EGR valve on a car: 1. The EGR valve stem rises, pushing the connected sliding contact arm to change its position, causing the sliding contact to move along the sliding resistor and generate different voltage signals. 2. This signal is transmitted to the engine control ECU, which monitors the position of the EGR valve to ensure the valve responds correctly to ECU commands. This adjusts and corrects the opening timing and duty cycle of the EGR valve, precisely controlling the recirculation volume to reduce emissions and improve performance. Here is additional information about EGR: 1. EGR stands for Exhaust Gas Recirculation system in engines, and the EGR valve is a key control component in the entire EGR system. 2. Based on whether feedback monitoring components are installed, the Exhaust Gas Recirculation (EGR) system can be divided into open-loop control EGR systems and closed-loop control EGR systems.
You see, the EGR valve in a car is actually a small valve, whose main purpose is to reduce engine emissions pollution. When the engine is running, this valve opens slightly, allowing some of the already burned exhaust gases to flow back into the intake system, where they mix with fresh air before re-entering the cylinders for combustion. Since these exhaust gases are high in temperature but low in oxygen, the combustion process slows down after mixing, lowering the overall temperature. As a result, the production of harmful gases like nitrogen oxides is reduced, making the car more environmentally friendly. I've seen many vehicles equipped with this device pass annual emission tests with ease, proving its practicality. While you might not notice it during normal driving, it works silently in traffic jams. However, carbon buildup over time can cause it to stick or malfunction, so regular maintenance and cleaning are advisable.
