2000 Cadillac El Dorado • V8 FWD Automatic • 79,000 miles

When I park my car facing downward in my drive way. Front end 1st. If I have less than a 1/4 tank of gas the sensor tells me I am low on fuel and only registers empty. Then when I pull out and drive for a while the gas gauge goes back up to around 1/4 or more. Wasn't able to start car today as a result of this. Is the fuel sensor in the back of the tank? Could this be a reason for this problem? I went and got gas in a can and filled the tank with 5 gallons. When I started the car and drove it to the station to get more gas it registered almost half a tank. What gives?
February 22, 2011.

You're running it too low and you are going to ruin your fuel pump that way. Keep more fuel in it.

Feb 22, 2011.
Ok, Thanks. I usually keep it at least 1/2 full. Just let it get low recently.

Feb 23, 2011.
U need a sending unit in the tank

Feb 25, 2011.