Why does the fuel gauge swing back and forth after starting the car?
2 Answers
It may be due to a malfunction in the fuel level sensor. It is recommended to visit a 4S store for inspection and repair as soon as possible. The car dashboard is a device that reflects the working conditions of various vehicle systems. Common indicators include the fuel indicator, washer fluid indicator, electronic throttle indicator, front and rear fog light indicators, and warning lights. Below is relevant information about the fuel level sensor: 1. The car fuel level sensor can float on the surface of the fuel layer, utilizing the lever principle. The other end of the float is a potentiometer. The amount of fuel determines the height of the float, and the potentiometer at the other end will reach different potentials based on the fuel level, which is then displayed on the dashboard. 2. The principle of the car fuel level sensor is based on a wound resistor, where the resistivity is determined by the material of the resistance wire, and the resistance value is determined by the material's resistivity and the number of coil turns.
I've encountered the issue of the fuel gauge needle swinging back and forth several times over my years of driving. The main cause is usually a stuck or worn fuel float in the tank - engine vibrations during startup make it swing irregularly instead of giving stable fuel level readings. Don't underestimate this swinging, as it can mislead your fuel judgment during normal driving and potentially leave you stranded, especially on long trips. In my case, I later discovered the float had accumulated too much debris, and cleaning it solved the problem. If the issue persists, I recommend visiting a repair shop to check whether you need a new float or wiring inspection - don't delay to avoid bigger problems. When parking, try choosing level ground for startups to reduce the swinging frequency.
