Fuel guage

[ddm156]

My fuel guage just lays low when I power the truck (tank is definitely full). It moves just so slightly, but that's it...moves from below E to E when I turn key to accessory or ignition.
Other guages appear to be in good working order. My temp guage only ever gets to about 170, but that is as long as I've had the truck. Oil fluctuates, but usually hangs at 40.
But fuel guage needs fixed. Since other guages working, I'm ruling out IVR.
I tested my sender by linking the hot and ground, at the sender. My fuel guage needle went totally full. So, before I order parts- is my likely culprit a bad fuel sender? I guess the sender was replaced 15 years ago, on a truck that's only been driven 4500 miles in that time....maybe it's a case of sitting around too much being bad for vehicles...?

 

[B RON CO]

Hi, you did the quick test when you grounded the wire and the gauge went full sweep. And you know the other gauges work. There is a ground back by the tank that you could check. The float in the tank could be sinking. I would remove the sender and move the arm to see what happens. Make sure the fuel level is low when you take the sender out. Good luck

 

[Oldtimer]

My aux tank sender behaved as you are describing yours.
Pulled the sender, and float was full of gas.
New float from JBG fixed it.