What is the working principle of an automotive high-pressure fuel pump?
2 Answers
The working principle of an automotive high-pressure fuel pump is: 1. Suction stroke: The downward movement of the pump piston provides the suction force, opening the inlet valve and drawing fuel into the pump chamber; 2. Return stroke: To control the actual fuel supply, the inlet valve remains open during the initial upward movement of the pump piston, allowing excess fuel to be pushed back to the low-pressure side; 3. Pumping stroke: Initially, the fuel pressure regulator valve is de-energized, causing the inlet valve to close under the combined action of the rising pressure in the pump chamber and the closing spring inside the valve. The functions of an automotive high-pressure fuel pump are: 1. To increase fuel pressure for high-pressure injection, achieving atomization; 2. To supply sufficient high-pressure fuel to the common rail.
The automotive high-pressure fuel pump operates much like the human heart pumping blood. I learned this from a mechanic friend. Simply put, it draws low-pressure fuel from the fuel tank, and through a piston driven by the camshaft or belt moving up and down, it compresses the fuel to extremely high pressure when the piston moves upward. The high-pressure fuel is then delivered through fuel lines to the injectors, where it is atomized into a fine mist before being injected into the cylinders, ensuring more complete combustion and stronger power. The ECU (Engine Control Unit) controls the opening and closing of the solenoid valve to regulate fuel quantity and pressure, ensuring high engine efficiency and fuel economy. Driving a turbocharged car, I clearly noticed how crucial this component is. If it malfunctions, causing engine hesitation or increased noise, it needs immediate replacement—otherwise, fuel consumption rises and engine damage may occur. Regularly inspecting the fuel pump seals and wiring can prevent oil leakage failures.
