Since replacing the fuel pump, the gauge reads full even when the tank is empty. Anyone have any ideas. Something to do with the fuel sending units? Could there be a wiring harness incorrectly attached?
If I remember it would be difficult to cross up the electrical plug since it can only plug one way. It's more likely to me if there was a wiring cross up it would be inside the cap at the 3 plugs. Or, it could be a mechanical issue where the float of one of the sending units is jammed. Either way sucks becuase pulling the tank is a pain. Attached are a couple of files from the manual that may give more insight. I will say that when my sending units were bad the gauge read empty. I replaced both of them and the pump while I had the tank out.
It could most definitely be a problem with your senders in the tank. For a temporary fix you could reset your odometer every time you refuel and just keep an eye on your miles once it gets close to 300 miles just refuel again. But it is just a temporary fix.