when i redid my gauges blue, i had the same problem. For me it was due to the fact that i had opened up the gauge pod and fooled around with it... and it sounds like you haven't. Maybe the previous owner did?
Anyways, what worked for me was taking the gauge cluster out, and adjusting the snap-rings around the needles, which is pretty easy to do. Just
1) undo the top two screws
2) take the surround out
3) then undo the three screws holding the gauges in place
4) unclip the three harnasses in the back
5) take the gauge pod out
6) Take the plastic cover off the gauge pod by undoing the black and clear clips holding onto the white backing of the gauge pod.
7) Now that your gauge faces are exposed, you can see upon further inspection that the needles have little snap rings around them. Kinda like little black washers. Make sure these are snapped tightly down. You can use a finger nail file or something along those lines to snap them down if they appear to be up. If they are up at all, this is what causes your needles to jump and not be smooth.
Hope that helped!