How to Test a Fuel Pump?
2 Answers
When a fuel pump fails, common symptoms include weak acceleration, jerking during sudden acceleration, buzzing noises while driving, illuminated engine warning light, and abnormal engine vibrations. Below are the causes of fuel pump damage: 1. Poor Oil Quality: It is highly likely due to the use of low-quality engine oil. Using higher-performance engine oil can moderately extend maintenance intervals while ensuring proper engine operation. If low-quality engine oil is used, severe wear may occur during engine operation, leading to noise and mechanical damage. 2. Clogged Oil Filter: If the oil filter is not replaced for an extended period, its blockage increases the fuel pump's oil supply pressure. The engine then operates under high-load conditions for prolonged periods, which can lead to fuel pump damage.
To check the fuel pump, I start with the simplest method: turn the key to the ON position without starting the engine before driving, and listen carefully for a buzzing sound near the fuel tank. If there's no sound, the pump might be faulty or there could be an electrical issue, such as a blown fuse or a malfunctioning relay. I would check the fuse box, locate the fuse corresponding to the fuel pump, see if it's blown, and try replacing it with a new one. If the pump makes noise but the car has difficulty starting or lacks power while driving, I would use a fuel pressure tester connected to the fuel rail to measure the pressure—normal readings should be between 30-50 psi. If the pressure is too low or fluctuates significantly, it indicates the pump is nearing the end of its life. When working on it myself, safety comes first: disconnect the battery's negative terminal to prevent sparks, and avoid smoking near the fuel tank. If I don't have the tools, I can check if the fuel filter is clogged; replacing the filter can extend the pump's lifespan.
