What is the function of the EGR valve?

1 Answers
StMalia
07/29/25 4:44pm
The function of the Exhaust Gas Recirculation (EGR) system is to reduce the emission of nitrogen oxides (NOX) in the exhaust. When the engine is operating under load, the EGR valve opens, allowing a small amount of exhaust gas to enter the intake manifold and mix with the combustible mixture before entering the combustion chamber. During idle, the EGR valve closes, and almost no exhaust gas is recirculated back into the engine. The EGR system primarily works through the following principles: 1. The CO2 and water vapor in the EGR significantly increase the specific heat capacity of the working medium. 2. The addition of exhaust gas also dilutes the oxygen concentration in the original mixture, slowing down the combustion speed. 3. It reduces both the peak and average temperatures during combustion, disrupting the favorable conditions for NO formation, thereby greatly reducing NOX emissions.
Was this review help?
4
1
Share
More Forum Discussions

Where is the transmission fluid filler port for the Buick Excelle?

The transmission fluid filler port for the Buick Excelle is located at the position of the right transmission half-shaft. You can loosen the screw labeled number 14 to fill the transmission fluid. Here is some relevant information about the Buick Excelle's transmission: 1. Regular Replacement: The transmission fluid of the Buick Excelle needs to be replaced regularly. The transmission relies on transmission fluid for cooling, lubrication, and hydraulic power transfer. If the transmission fluid is used for too long, it will reduce the performance of the transmission. Severely contaminated transmission fluid can also lead to a series of transmission issues. 2. Transmission Size: Taking the Buick Excelle 2020 15N CVT Luxury National VI as an example: It is a compact 4-door, 5-seater sedan with a top speed of 170 km/h, equipped with a CVT continuously variable transmission. The Buick Excelle 2020 15N CVT Luxury National VI has a length, width, and height of 4468mm, 1765mm, and 1469mm respectively, a wheelbase of 2611mm, and a fuel tank capacity of 40L.
4
5
Share

Which cars support Huawei HiCar?

Volvo, Geely, BYD, Great Wall Motors and other car brands support Huawei HiCar. The following is a related introduction about Huawei HiCar: 1. Technical features: HUAWEI HiCar connects mobile phones and cars based on three-layer standards and capabilities, building a mutual assistance resource pool between mobile phones and cars, extending the mobile phone's service ecosystem to the car, achieving the optimal human-machine interaction experience of "mobile phone + car machine", the interconnection and seamless connection & service flow of "mobile phone + car machine + N terminals", and the optimal experience brought by optimal hardware resources; on the other hand, HUAWEI HiCar builds a one-stop development open ecological platform. 2. Basic introduction: From the perspective of cars, the car cockpit has the display capability of the car's central control large screen, instrument/HUD multi-screen, better audio input and output capabilities such as microphones/speakers, convenient reverse control input capabilities such as steering wheel buttons and knobs, and high-precision vehicle data. However, the hardware computing power upgrade cycle of the car cockpit central control host is relatively long, and the applications and services in the car are not rich enough.
2
2
Share

What is the fuel tank capacity of the GLK300?

The fuel tank capacity of the Mercedes-Benz GLK300 is 66 liters, as officially announced. The GLK300 requires 95-octane fuel, with a fuel consumption of 8.5-10.9L per 100 kilometers. A full tank can provide a driving range of 605-776km. During daily driving, it is important to monitor the remaining fuel level. This is typically done by observing the fuel gauge inside the vehicle. Under normal circumstances, the fuel level will be accurately reflected on the gauge. The fuel gauge usually has 5 to 6 segments. It is advisable to refuel when there are only 2 segments left to avoid running out of fuel midway. In practice, the actual amount of fuel filled may exceed the nominal capacity. This is because the manufacturer's specified tank capacity is measured from the bottom of the tank to the safety limit. There is additional space from the safety limit to the tank opening, designed to allow for fuel expansion due to temperature increases without causing overflow. If fuel is filled up to the tank opening, the actual amount of fuel added may exceed the nominal tank capacity.
20
1
Share

How can beginners avoid stalling when driving?

Beginners can avoid stalling by properly controlling the clutch, applying the throttle, and using the handbrake in coordination. Here are the details: 1. Control the clutch properly: When starting the car, controlling the clutch is key to avoiding stalling. Beginners often struggle with clutch control, especially in manual transmission cars. If the clutch is released too slowly, the car may stall. Therefore, when starting, press the clutch pedal firmly with your left foot, hold it steady halfway, and then slowly release it as the car begins to move. 2. Apply the throttle: While controlling the clutch, applying the throttle is also crucial. Simply releasing the clutch without applying the throttle can cause the car to move too slowly and stall. Hence, gently press the throttle while releasing the clutch to ensure a smoother start. 3. Use the handbrake in coordination: Sometimes, beginners may experience the car rolling back when starting, which can cause panic and lead to stalling. In such cases, use the handbrake. Before shifting into gear, pull the handbrake tight, then release the clutch halfway, let go of the handbrake, and apply the throttle. This method prevents the car from rolling back during startup.
2
5
Share

Is the Vehicle Purchase Tax Calculated Based on the Naked Car Price or the Manufacturer's Suggested Retail Price?

This is not necessarily the case. The calculation method for the vehicle purchase tax is based on the "minimum taxable price." To put it simply, the specific amount of the purchase tax is not calculated based on the manufacturer's suggested retail price, but rather on the naked car purchase price (i.e., the price on the purchase invoice). Only when the invoice price is lower than the minimum taxable price will the tax be levied based on the minimum taxable price. Additional information is as follows: 1. Tax Payment Location: For purchasing taxable vehicles, the tax should be declared and paid to the competent tax authority in the vehicle registration location. For purchasing taxable vehicles that do not require registration procedures, the tax should be declared and paid to the competent tax authority in the taxpayer's location. 2. Management Method: When filing a tax return, taxpayers must truthfully fill out the "Vehicle Purchase Tax Return Form" and provide the original and photocopies of the following documents. The photocopies and the tax payment copy of the "Uniform Invoice for Motor Vehicle Sales" will be retained by the competent tax authority, while other original documents will be returned to the taxpayer after review by the competent tax authority.
1
2
Share

What to Do When There Are Fine Cracks on the Side of Car Tires?

Cracks are minor and can be used normally. If there are many deep cracks, then it is necessary to replace the new tires. The normal lifespan of tires is generally three years. For those who frequently drive, it is recommended to replace the tires every two years. Harder tires and more wear-resistant tires are more prone to cracking. Common abnormal wear includes the following: 1. Early wear in the central part of the tire: The main reason is excessive inflation. Appropriately increasing the inflation of the tire can reduce the rolling resistance of the tire and save fuel. When the inflation is too high, it not only affects the shock absorption performance of the tire but also causes excessive deformation of the tire, reducing the contact area with the ground. Normal wear can only be borne by the central part of the tread, resulting in early wear. If wide tires are selected on narrow rims, it can also cause early wear in the central part. 2. Excessive wear on both sides of the tire: The main reasons are insufficient inflation or long-term overload driving. When the inflation is low or the load is heavy, the contact area between the tire and the ground increases, causing both sides of the tire to come into contact with the ground and participate in work, resulting in early wear. 3. Excessive wear on one side of the tire: The main reason is inaccurate front wheel alignment. When the camber angle of the front wheels is too large, the outer side of the tire experiences early wear. When the camber angle is too small or absent, the inner side of the tire experiences early wear.
9
3
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.