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What is the working principle of an engine vacuum system?

5 Answers
SanAustin
07/25/25 5:49am

The working principle of an engine vacuum system is that the vacuum pump generates vacuum for the brake booster and for controlling the exhaust gas bypass valve. The recirculation air pressure relief valve also obtains vacuum through an electric switching valve (EUV). The vacuum pump mainly consists of components such as the pump body, rotor, vanes, and intake and exhaust ports. It refers to a device or equipment that uses mechanical, physical, chemical, or physicochemical methods to evacuate a container and achieve a vacuum. Functions of the engine vacuum pump: The function of the vacuum pump is to create negative pressure, thereby increasing braking force. The vacuum pump in a car generator is generally an oil pump, meaning the vacuum pump core rotates together with the generator shaft. By continuously sucking and pumping oil, negative pressure, or a vacuum, is created inside the vacuum pump housing. A vacuum pump is a device that improves, generates, and maintains a vacuum in a sealed space using various methods. Based on their working principles, vacuum pumps can be broadly classified into two types: gas capture pumps and gas transfer pumps. They are widely used in industries such as metallurgy, chemicals, food, and electronic coating.

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DelCamilla
08/11/25 12:52pm

I find the working principle of the engine vacuum system quite fascinating. Simply put, when the engine is running, the piston moves downward to draw in air through the intake manifold, where the pressure is lower than the outside atmospheric pressure, creating a state of negative pressure, which we call vacuum. This vacuum force isn't just for show—it powers many small devices, such as the brake booster, making it easier and less strenuous to apply the brakes. It also aids emission systems like the PCV valve, helping to recirculate oil vapors inside the engine, reducing pollution and waste. While studying cars, I realized why vacuum leaks can cause major issues—if the hoses age and develop leaks, the engine may idle roughly, or you might even notice harder brakes and reduced power. Older cars, in particular, need extra attention in this regard, with regular checks to ensure hose connections are secure to avoid safety hazards. Whenever I drive, I always keep an eye out for any signs of trouble in this area.

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SimonDella
09/27/25 5:01am

After years of car enthusiasm, I'm no stranger to engine vacuum systems. It operates on the negative pressure created by piston suction – simply put, low pressure in the manifold generates vacuum force. What's this vacuum used for? Things like power brakes that save your effort, and it also controls crankcase ventilation. I've personally experienced a vacuum leak where the idle went rough and the brake pedal turned rock-hard, nearly causing an accident. A quick inspection revealed a cracked vacuum hose, which I replaced with new rubber tubing. Here's my advice: never underestimate this small but critical system that keeps various auxiliary functions running smoothly. A simple periodic check during maintenance can prevent major headaches – don't wait until you need expensive repairs.

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DiOlive
11/10/25 7:01am

The working principle of the vacuum system is essentially that the engine's piston creates a vacuum by suction during operation, which drives components like the brake booster. The key is to avoid air leaks, as aging pipelines are prone to failure. Regular checks on sealing integrity are recommended.

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OLeilani
12/31/25 8:45am

I've been paying attention to automotive environmental protection, and the vacuum system plays a crucial role in reducing emissions. The vacuum formed by piston intake is used for devices like the PCV valve, effectively recycling engine waste oil and gas to reduce pollution. Regular maintenance can be a great help.

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