Why does the fuel gauge needle only rise halfway when the tank is full?
1 Answers
The reason why the fuel gauge needle only rises halfway when the tank is full is: the sliding rheostat's contact is rusty, causing excessive resistance, and it can be fixed by replacing it with a new one. How the car fuel gauge works: The fuel gauge is essentially an ammeter. When the tank is full, the float pushes the contact up, reducing the resistance, which increases the current reading, and the fuel gauge reading also increases. Conversely, when the fuel level drops, the resistance increases, and the reading decreases. When there is too much fuel in the tank, the fuel may evaporate due to rising temperatures, increasing the pressure inside the tank, which can have a certain impact on the tank. Additionally, fuel evaporation can cause some damage to the fuel vapor absorption system in the tank, and the evaporated fuel also directly leads to fuel wastage.