This is similar to the fuel gauge problem thread, but this is slightly different.

I was going on a roadtrip and i managed to pull 400miles on a half a tank of gas. I filled up the baby before the trip and when the needle hit the median mark, the Odo. read 400 Miles... i was like this is crazy. While I was driving however, the gas light came on while i was going 90mph yet the fuel gauge said that the fuel tank was still half full.

Next morning, i started the car and the needle dipped below the "E" and the gas light turned on. I was like, :wtf: because last night I still had half a tank of gas. I went to refuel it and the pump said that i fueled up 15.6 gallons. jeez, whats up this??