What are the symptoms of insufficient gasoline pressure?

[VonAdriel]

The symptoms of insufficient fuel pump pressure include the fuel pump making a "buzzing" abnormal noise. The vehicle experiences weak acceleration, especially with noticeable jerking during sudden acceleration. Difficulty starting the vehicle or failure to start may occur. The engine warning light on the vehicle's combination meter remains constantly illuminated. Below are relevant details about the fuel pump: Working principle of the fuel pressure pump: Oil pressure is regulated by the coordination between the spring and vacuum degree in the air chamber. When oil pressure exceeds the standard value, high-pressure fuel moves the diaphragm upward, opening the ball valve and allowing excess fuel to return through the return pipe. When pressure falls below the standard value, the spring presses the diaphragm to close the ball valve, stopping fuel return. The pressure regulator's function is to maintain constant pressure in the fuel circuit. Method for detecting automotive fuel pressure: Turn the ignition switch on (without starting the engine) to operate the electric fuel pump. The fuel pressure at this time should meet technical requirements, generally fluctuating around 0.3MPa.