On my truck I have had a wandering fuel level gauge for a while now and I am going to try and fix the problem, I think it is probably a grounding issue because the Temp needle will occasionally have fits of its own.

Does anyone have a schematic of the instrument cluster circuit board and the Message Center?

Our instrument clusters no not have a voltage regulator do they?
Where do you usually find the problems, the wiring under the dash or by the fuel tank?
I hate intermittent problems; it is easier if it doesn't work at all. I will probably add a few new ground points to the harness at the cluster.
Thanks Jim

 

Your problem could also be corrosion in that big square plug that goes through the fire-wall, close to the brake-booster.