In most cases the fuel gauge sending unit in the fuel tank has failed.
25 gallons ========================================================= The 1999 Ford Windstar Owner Guide shows ( 26.0 U.S. gallons ) Helpfull
The 1999 Ford Windstar does not have a separate computer for the fuel system. The vehicle computer contains all of the functions for the fuel system. The vehicle system computer is located behind the kick plate.
On a 1999 Ford Windstar : ( relay # 207 is the fuel pump relay ) In the Power Distribution Box ( which is " live " ) located in the front of your engine compartment , near the battery
its on the fuel rail, it actually takes temperature of the rail not fuel.
Drive it until it runs out
gage is the best (kon )
Behind the service panel on the right side of the cargo area
I believe the descriptor is: Evap Low Pressure (related to fuel tank)
If you have the instrument panel with the tachometer , just above and to the left of the tachometer is a " check gage " light that comes on if the oil pressure is too low , the engine coolant temperature is too high , or your gas gauge is at or near empty
The check gage light ( if equipped ) lights up if the fuel tank is at or near empty , the engine coolant temperature is high , or the oil pressure is low
Either : The engine coolant temperature is HIGH The engine oil pressure is LOW Or the fuel gauge is at or near EMPTY
Not surprisingly, there is no drain plug - so you'll be using something like a siphon hose.There is one other alternative: drive it until it's empty - that what my wife does...