Fuel gauge reading empty

I’d start with the fuel level sender in the tank. If the gauge stays on empty even after filling up, the sender may be stuck or the wiring/connector could be bad.

You can also check the fuse and the connector at the tank, but on these trucks the sender is a pretty common suspect. If the gauge suddenly dropped to empty, I’d look there first.

@naomigrant let's make sure the gauge itself on the dashboard isn't broken. Try this:

Press and hold the trip reset button on your instrument cluster, turn the ignition key to the "On" position without starting the engine, and wait for "TEST" to appear on the odometer. Let go of the button. All the needles should sweep all the way up and back down. If the fuel needle sweeps smoothly, your dashboard is fine. If not you know you have an issue with the fuel gauge itself.

After that it most likely is an issue with the fuel sending unit inside the tank. To work on that you will need to drop the tank. Here are the files from the SM that deal with that 2006 F 150 Mark LT Fuel Pump Module2006 F 150 Fuel Level Sensor2006 F 150 Fuel Tank Filler Pipe2006 F 150 Fuel Tank

Let us know what you find out.

While you work on your F-150, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person who has the same issues with their device. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

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