What Is a Fuel Sender?

Many components in our vehicles help them operate properly and usually together. One such component is the fuel sender -- a device that may vary in placement and size from vehicle to vehicle but always performs the same function.

Fuel Sender

The fuel sender resides in the fuel tank and consists of a float, which is attached to a long metal rod attached to a variable resistor. This resistor measures the amount of pressure the float puts on the bar. As the fuel goes down, the float goes down with it.

Purpose

The fuel sender helps measure the amount of fuel in your tank. As it dips, the electrical current in the variable resistor sends weaker electrical signals to your fuel gauge. The gauge will then drop accordingly.

Problems

The fuel sender may give inaccurate readings to your fuel gauge, which can be problematic if you are running low on gas. It takes awhile for the fuel sender to drop, which may make it seem like you have more gas than you actually do. However, the fuel may also dip to its lowest point before you are actually out of gas.

References

• Parts Train: Fuel Sending Unit
• Car Dictionary: Fuel Tank Sender