Bump.

i put new gauege in my boat the same thing happen to me it was the ground wires there were piggy back one was connected to the other . i hook them up to there own wire .now they work great

yes sounds like a ground problem, try and use only one point and dedicated ground wires.

I know that all the grounds for the gauges are piggy backed then joined to the one ground wire coming from the back of the boat. I should seperate all the grounds and run them individually to the ground wire or run the individual ground wires all the way to the battery?

Run a good sized awg of wire from the engine block up to the helm and use a ground bus bar.