What are the symptoms of a bad fuel pump?

2 Answers
DeLilliana
07/24/25 10:19am
Symptoms of a bad fuel pump: 1. Weak acceleration with a jerking sensation when accelerating sharply; 2. Difficulty starting; 3. A buzzing noise while driving; 4. The engine warning light is on; 5. Engine shaking. Causes of fuel pump damage: 1. When fuel quality is poor, various impurities in the fuel tank can be sucked into the fuel pump motor, causing damage; 2. Waiting until the fuel light comes on to refuel, which can cause the fuel pump to be in a low position, lacking sufficient cooling and lubrication; 3. Long-term failure to replace the fuel filter, leading to severe blockage in the fuel supply system, making the fuel pump work harder and eventually causing damage due to prolonged high-load operation.
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Taylor
08/11/25 5:27am
I've been driving for over a decade and experienced the embarrassing situation of a fuel pump failure. The symptoms were very obvious: First, difficulty starting - that morning it took five or six attempts to barely get the engine running, feeling like the fuel wasn't being delivered properly. Then, acceleration became sluggish while driving, struggling even on gentle slopes like driving on soft sand. At idle, the engine shook unsteadily and even stalled by the roadside. Finally, I heard strange buzzing noises from under the chassis, like an electric motor wailing. If not addressed promptly, it could trigger engine overheating warnings, and in severe cases, damage the fuel injectors. That time, I had it towed to the repair shop and spent 500 yuan replacing the pump, which finally solved the problem. Don't underestimate this issue - early detection can prevent breakdowns.
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