My suggestions are:
If you replaced those parts with used ones, then maybe those parts are bad too.
If you bought them new, then double or triple check to make sure it's all hooked up correctly.
If that's been done, then my only other thought is that the gauge itself is defective. IDK if that entails replacing the whole insturment cluster as a unit, or if you can replace just the gauge. I've never looked at one enough to figure that out.
I know that I didn't really offer anything you probably haven't already thought of or done, but I hope it helps and I hope you figure it out. Good Luck!