Ford Repair: 1993 Ford Taurus Fuel Gauge, 1980s 1990s, ford taurus

Question
I have 1993 Ford Taurus with a 3.0L Engine.My fuel gauge stays on over full any time the key is on and drops to full mark when the key is off what would cause this and how can it be fixed???

Answer
The most likely cause is a stuck or worn out fuel gauge sending unit, which is in the tank and part of the fuel pump assembly. In very rare cases the gauge could be faulty, but I would replace the sending unit first.

I did hundreds of these fuel pumps when at the dealer in the 1980s-1990s.