My volt gauge doesn't want to fall all the way down when the car is turned off. It will just fall below the halfway mark and stay there, so when you crank the car the next time, the needle shoots up and basically maxes out. It just started doing this out of nowhere, worked correctly before. I took the plastic cover off and lightly touched the hand and it fell right down where it should be. Cranked it up and the gauge was correct, but when I turned it off again it got stuck a little below halfway so its back to where it was. Any idea on why its doing this? Thanks!