What Causes the Engine to Be Noisy After Refueling?
2 Answers
Car engine becomes noisy after refueling due to the following reasons: 1. Oil issue: The engine oil has not fully lubricated all components of the engine. It takes some time for the new oil to evenly lubricate all parts of the engine. 2. Severe wear: It could also be due to severe wear, and if the engine internals are cleaned, the gaps from wear may become larger. If maintenance is neglected, it might be caused by excessive carbon buildup in the engine (such as excessive carbon in the engine, throttle, spark plugs, etc.), which can be resolved by cleaning at a repair shop. 3. Exhaust pipe leak: When there is a leak in the intake or exhaust pipe, the vehicle produces a louder roar as the exhaust rate increases with acceleration.
I've experienced the engine getting louder after refueling several times, usually due to poor fuel quality with excessive impurities causing incomplete combustion. My car is an older family sedan, and every time I fill up with cheap gas from small stations, problems arise - the engine noise increases and sometimes comes with vibrations. The repair shop checked it and said the fuel system was adapting to the new fuel, possibly with unstable fuel pump pressure or spark plug carbon buildup exacerbating the noise. They recommended switching to reputable gas stations and avoiding cheap options, suggesting the noise might normalize after running through one or two tanks. If the noise persists, it's best to have a mechanic thoroughly inspect the fuel system and ignition system to prevent engine damage. For safety, I now always verify the fuel grade label before refueling, and this issue has basically stopped occurring.