i have a 2011 sierra 1500 z71 ext cab.
I had once noticed my fuel gauge go empty then was acting odd and ran a cleaner with next fill up and the problem went away.
Now about 5-6 months later it happened again. The gauge goes from normal to empty. then will slowly come back up, or will jump back up, then can read correctly, then falls back to empty.
The gauge reading empty will put CEL on. The gauge will work again while CEL is on, then it will go down, slowly come up etc...
Each time i have filled up since it started recently, it was either at empty or had been going back and fourth. first fill up of 10 gallons and it seemed to be working again normally. CEL light went off, and gauge read fine.
2 days later its acting up. CEL comes back on.
I fill up again, and all is normal. Now again few days later and CEL comes out. gauge works sometimes and will move extremely slow back to the correct spot.
I havent gotten under to do diagnostics but i wasnt sure if anyone knew if it was a problem with a float device, or ground wire, sensor?
I have researched and i would imagine ground wire but seems sensors are often bad too.
Thanks for any input