I have a 2007 pontiac Grand Prix the fuel gauge goes to full when on empty
Sender is most likely the problem, if you can gain access to the sender plug on the fuel tank, unplug it and turn the key on, do not attempt to start it, the fuel gauge should climb right past full and go all the way to the stop if the gauge has one, If it does this then the sender is at fault, if it don't then it is either a gauge problem or a wiring problem.
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