There’s something satisfying about fixing parts on your car yourself — especially when it’s something that most folks don’t even think about until it stops working. One of those parts is the fuel sender. If your fuel gauge is acting up, there’s a good chance the sender is the problem. Tackling an [electric fuel sender repair](https://) can feel intimidating at first, but it’s a doable project for any DIYer who’s patient, careful, and willing to get a little fuel on their hands. Most classic and older vehicles use simple electric fuel senders. These small but important devices sit inside your fuel tank, measuring how much gas you have and sending that info to your gauge. When they stop working, your gauge can get stuck on full, empty, or bounce around without making sense. In this guide, you’ll learn how these senders work, how to test them, and what you can do to get yours working again. How an Electric Fuel Sender Works Before you break out your tools, it helps to understand what’s going on inside the tank. An electric fuel sender is a simple device, but it does an important job. Inside the sender is a float — usually made of cork, plastic, or foam — attached to a metal arm. That arm moves up and down as the fuel level changes. maxresdefault (1) This motion changes the resistance in a small variable resistor called a rheostat. That changing resistance sends a signal to your fuel gauge. When everything’s working right, the gauge matches the position of the float pretty accurately.