my gauge is always reading 1/4- 1/2. I have all new parts from sending unit to gauge. Gauge being the last thing I bought. ungrounded it moves freely spiking to full. Grounding it brings it back down between 1/4 and 1/2. Original gauge did the same and that was the last part I replaced in my trouble shooting. The sending unit reads 0-30 ohms on my multimeter. when I pulled the gauge out to make sure the needle wasn't stuck on the glass that didn't make a difference. working the float by hand doesn't move the needle either. any ideas here?