How to Determine if the Fuel Pump is Leaking Pressure?
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Signs of slight fuel pump pressure leakage include the engine lacking power during acceleration; difficulty starting the car, requiring multiple ignition attempts; uneven or shaky engine rotation; a humming noise while driving; a jerking sensation during sudden acceleration; and inaccurate fuel level indicators. Below is more detailed information about the fuel pump: Function of the Fuel Pump: It draws gasoline from the fuel tank and delivers it through the pipeline and fuel filter to the carburetor's float chamber. Thanks to the fuel pump, the fuel tank can be placed at the rear of the car, far from the engine and below it. Fuel pumps can be categorized into two types based on their driving mechanisms: mechanically driven diaphragm type and electrically driven type. Identifying the Fuel Pump: There are two fuel pump wires: one for power supply and one for grounding. The fuel pump operates with a high current, so its wires are thicker, while the sensor wires are thinner, making them easy to distinguish.
I've been driving for over 20 years. Last time when I had fuel pump issues, the engine was extremely difficult to start—it took five or six attempts to fire up, and it idled with severe vibrations while acceleration felt like being choked. The mechanic taught me how to check for pressure leaks: Listen for the fuel pump sound before ignition (normal operation produces a buzzing noise); after ignition, observe if the fuel pressure gauge drops rapidly (normal pressure should stabilize around 2-5 kg). If it drops quickly, feel around the fuel pump for wetness or gasoline smell—I once discovered oil seepage from the pump body. If left unfixed, this issue can cause fuel consumption to skyrocket and even lead to breakdowns on highways. I now keep a simple fuel pressure tester and perform regular checks to prevent major repairs. That experience left a lasting lesson—I've naturally developed the habit of inspecting the fuel system every three months.