Troubleshooting fuel gauge

I only get to really work on the taco over the weekends so I'm starting to plan out to tackling this job this upcoming Saturday.

My fuel gauge has been dead since I bought this truck. All other gauges on the cluster are fine so its probably not the ground points. I'm going to check the sending unit wiring and see if that is loose or broken and hope its not the unit itself.

On reading some threads it seems that some recommend checking the plug where the wiring connects to the sending unit. What is the easiest way to get to that point? Would accessing that area require me taking off the bed or can I get to there by crawling under the truck?

If this turns out to be more trouble than it's worth, I was leaning towards leaving it as-is and putting in a scanguage or ultra-gauge and having that give me the readout I would need and more.

 

You can get the wiring through the wheel well. I haven't been under there in a while, but I think you may also be able to get to it from under the truck, but you'll need to get the driveshaft out of the way.

 

I haven't addressed this as yet but wanted to bring this wrinkle to this issue. I did look and see where the wiring was coming from the tank from the driver side rear wheel well. Looks tight but I think I could get to it.

One thing I am noticing as I drive this truck more, the need that has been pegged on E when the tank is full, is slowly creeping upward, so its almost to the last marker now. Anyone seen behavior like this?