After driving her the past two days, the thermostat gauge is acting realllly strange ALL the time; It'll start reading at the bottom, and then work its way up to the 80 degree mark, but usually at that point, it'll JUMP to over 120 degrees, and while highway driving, it'll move anywhere between 80 and 120, and I have to hit the dash to make it unstick from the 120 degree mark.

I guess I need a new Thermostat? Probably a coolant flush while I'm at it.