Why is the fuel gauge not moving?
2 Answers
There are several reasons why the fuel gauge may not move: the fuel float may be stuck, aged, or damaged, causing it to fail to float on the gasoline. Instead, it may remain suspended in the fuel or sink to the bottom, leading to inaccurate measurements or no response. The solution is to remove and inspect the fuel pump. The working principle of the fuel gauge: Inside the car's fuel tank, there is a float ball (fuel float) connected to a sliding resistor. As the fuel level changes, the potential at the measurement terminal varies accordingly. The car's instrument processes this signal and displays the corresponding value, which represents the remaining fuel in the tank. Other symptoms of fuel gauge malfunction include the gauge showing higher or lower than actual levels, or fluctuating readings while driving.
I've been driving for decades and have encountered the issue of the fuel gauge not moving several times. The most common cause is the fuel float getting stuck, possibly due to the strong impact during refueling or impurities in the fuel tank preventing the float from moving. Sometimes, it's an electrical issue, such as a blown fuse, especially in older vehicles where wiring can deteriorate and short-circuit. It's also possible for the dashboard itself to malfunction. Once, on the highway, my fuel gauge stayed stuck, and I nearly ran out of gas relying on my experience to estimate the fuel level—it was really dangerous. I recommend driving for a while to see if the needle resets; check the corresponding fuse in the fuse box; if that doesn’t work, head to a repair shop immediately to inspect the float and wiring. Safety first—don’t delay.