Commonly used and self-explanatory, your car’s fuel gauge approximates the amount of gasoline remaining in your tank. In most modern vehicles, the fuel gauge will also include a warning light that will illuminate when gasoline levels are dangerously low. You should not continually allow fuel to reach dangerously low levels before refueling, because your car’s fuel pump is immersed in gasoline, which acts as a coolant for the pump. If fuel is low, the pump can be exposed to air and overheat, possibly leading to pump failure. Therefore, your car’s fuel gauge needs to be constantly monitored.