I got a "refurbished" DIC off eBay. When I plugged it in, the fuel range and average MPG read zero. Everything else was fine. When I got it up on the highway tonight, it worked a little--showed range of 3 miles and .7 MPG.
Then, when I filled the gas tank, it instantly started working completely correctly. (I'm 99% sure the sender is working, because the instant MPG always worked.) What caused this, and is it likely to happen again when the fuel level drops?