What is the function of the fuel pressure valve?

1 Answers
DiNora
07/30/25 4:00am
The function of the fuel pressure valve is: 1. To regulate the fuel pressure in the fuel supply system, maintaining a constant pressure difference between the system fuel pressure and the intake manifold pressure; 2. To buffer the pressure pulsations generated by the fuel pump during fuel supply and the pressure fluctuations caused by intermittent fuel injection from the injectors. The fuel pressure valve is also known as the fuel pressure regulator. The automotive fuel pressure regulator is a component of modern vehicles, belonging to the fuel supply system of electronically controlled engines, and is typically installed on the return pipe side of the fuel rail. The working principle of the fuel pressure regulator is that when the fuel pressure exceeds the standard value, high-pressure fuel pushes the diaphragm upward, opening the ball valve, and excess fuel flows back to the fuel tank through the return pipe. When the pressure falls below the standard value, the spring presses the diaphragm downward to close the ball valve, stopping the return flow.
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