I've since heard of other ways but here is how I stopped mine from sticking (from memory, three years ago...)
Take the gauge completely out and to the kitchen table. Take two very small brads (tiny nails) and cut them off to where, with the heads on the gauge face, they barely stick up above the pointer. Decide where to put the brads so that they will not restrict normal movement but will stop overtravel. One tiny drop of super-glue does the trick. After the glue dries, touch up the brads with flat black paint.
Sounds Mickey Mouse but mine doesn't stick anymore.
From: JJJ