My gas guage is way off, shows 1/4 tank when I have in 3/4 tank, everyone says it might be the float on the pump, well I took the whole pump out and there is no float. just the pump, the bracket its on, and the filter at the end. but over to the side inside the tank was like a metal arm that went up and down, is that the float?

 

ok well it moves up and down just fine, I could barely fit my hand in there and I was trying to feel the end, I assume the end has a senosr of some sort to tell the cluster how much fuel is in the tank right? if so how do I check it?