What are the signs of a faulty fuel level sensor?

[FinleyRose]

The signs of a faulty fuel level sensor are: 1. The car's fuel gauge suddenly drops to zero; 2. The car's fuel gauge remains stuck at a certain position. The fuel level sensor is a fuel float, which is a sensing device for fuel level height. It is usually integrated with the fuel pump and works together with the fuel gauge to form the car's fuel level detection system. The car's fuel tank contains a float connected by a thin metal rod, typically made of foam plastic. The end of the metal rod is attached to a variable resistor. A resistor is a device used to impede the flow of electric current; the greater the resistance, the smaller the current that passes through. In the fuel tank, the variable resistor consists of a strip of resistive material with one end grounded. A wiper arm connected to the fuel gauge slides along the resistive material strip, thereby conducting current from the fuel gauge to the resistor.