Ground the pink sender wire with key on. Gauge should go all full if it is good. This is indicating the sender is bad. If the gauge does not go all full knowing their is voltage at the sender, the gauge is bad or you have a bad connection at the gauge.
“The world will not be destroyed by those who do evil, but by those who watch them without doing anything” Remember what He has done and remember that He is not done yet! GOD IS GOOD