Hey bro, this may help you use the process of elimination to figure out if it's a failed guage or fuel sensor.
The following is a copy of a previous post....
Hey guys, I want to expose this little secret to the Mopar brotherhood for us Dodge/Chrysler guys. Many of you may already know this but here is a very cool thing.
Hold down your Tripometer/Trip reset button/push stick while your vehicle is off, put the keys to the ON position, don't turn them enough to get the stereo or AC/Heat going, just to the ON position! Let go, wait a couple seconds and watch your Instruments, LED's & Gauges! Your care will look like it has a mind of it's own! It should test all of your Instruments, LED'& Gauges in your dash console above your steering wheel. This is how the dealers usually test functionality! I love this, it looks so tight! If you do it at night or in the dark you can also turn your parking lights on to light up your Instruments & Gauges so you can see
I had a problem when my gas guage would go to 0, ding, & go back to where it was. It just needed a fuel sending KIT!. The key word is KIT! The OTHER dealer wanted to sell me a whole fuel assembly for $600. Turns out kit was available & the parts box was dated 1997. Gee guess it's been around awhile! Don't let them tell you that you need the whole 600 dollar fuel sending unit. You may not.