stumped and out $115

I thought the fuel sending unit on my 97 gt 3800 was bad as it was pegged low but would peg hi if I unplugged it. I replaced it today and it is still pegged low. Doesn't the fuel sending unit run through the pcm? Could this be the problem. I didn't find any thing grounded when I checked the plug to ground - that would be the purple wire. The voltage to the fuel sending unit was about 10 volts. I was expecting it to be closer to 12 but it should still read at 10 shouldn't it?:confused: