A faulty fuel pump has several distinct symptoms associated with it, through which the driver can tell the system may not be up to supplying the right amount of fuel in the engine. The first noticeable thing when it starts to develop an issue is sputtering. The car may jerk while driving or hesitate/stall whenever accelerating hard. A report by Consumer Reports in 2021 noted that nearly 14% of cars experience sputtering when a fuel pump is failing. Another common symptom of a bad fuel pump is difficulty starting the engine. The fuel pump always provides continuous fuel flow to the engine. However, when there is a malfunctioning fuel pump, it will fail to provide adequate fuel to burn as the engine needs it and may take some time just to crank or not start altogether. Fuel pump failure was proved by studies as one of the top five causes of start failures in vehicles. According to one 2020 analysis by the Car Care Council, about 20% of all breakdowns are related to problems in the fuel system, with the fuel pump playing a significant role.
Fuel pressure problems, such as loss of pressure, are another warning sign of a faulty fuel pump. This can be observed with a fuel pressure gauge. The common operating pressure of a conventional fuel system is around 40 to 60 psi for most types, which again depends on models. The fuel pressure lower than this range could suggest some faults either in the Fuel Pump or clogged fuel filters. Experts from the ASA advise doing a pressure test as proof of fuel supply malfunctioning in such conditions.
Besides, strange noises from the fuel tank area can also signal that the pump is malfunctioning. If the fuel pump is making whining or buzzing sounds, it could indicate that the internal components are wearing out or the pump is struggling to push fuel through the lines. These noises often become louder as the failure progresses.
Furthermore, the car may show poor fuel economy or a sudden decline in gas mileage when the fuel pump is not functioning right. The pump might not deliver the proper amount of fuel to the engine, which in turn forces the engine to work harder to maintain performance. This alone can decrease fuel economy by as much as 10-15%, according to a report by the Department of Energy.
When these issues occur, it is essential to address the situation promptly to avoid further engine damage. A defective fuel pump can lead to engine misfires, overheating, or complete engine failure if not fixed. Mechanics often advise inspecting the Fuel Pump and other components like the fuel filter or fuel lines to confirm the exact cause of the issue.
