The fuel sender unit functions to measure the level of fuel in the fuel tank. Its purpose is to provide the driver with accurate fuel level read outs to help prevent the car running out of fuel.
Usually attached to the fuel pump, and normally located in the fuel tank, the fuel sender unit measures the level of fuel in the tank, usually with the aid of a float and a clever resistor-type sensor.
The fuel level data is sent to the car's fuel gauge, normally located on the dashboard. The fuel gauge shows the level of fuel in the tank. As the fuel is used, the floats lower in the fuel sender unit and the fuel gauge reflects this by slowly moving down. This enables the driver to see how much fuel is left in the tank. The driver would use this information to fill the car up with fuel as and when required. It helps the driver to make sure the fuel levels don't get too low. The worst case scenario is running out of fuel. Running out of fuel can damage the engine. Running a car on low levels of fuel can also be harmful to engine components and the fuel system, including the fuel filter and fuel pump.
Problems with the fuel system should be fixed as soon as possible. If the fuel sender unit is faulty this can affect the accuracy of the information displayed on the fuel gauge and could lead to the car running out of fuel. When replacing this part, it is vital that the replacement part is compatible with the car. Specifically engineered for the make and model of your vehicle, the fuel sender unit is the ideal choice.