Gas gauge showing full when it's not...

[J444HN]

The gauge on my truck is showing full when it's not.
I know what you're thinking...stepper motors but they have all just been done.
Everything was fine til my fuel pump on the tank was corroded and leaking at the top.
Put a new pump and sender unit in and it was fine for a day or so then the full tank problem started.
Sent that pump and sender back and got a new one. Fine for a week then the same happened again!
What could be telling it that it's full.
Also tried another speedometer just to be sure but it's definitely not that.

Please help

 

[Rocket Man]

Probably the aftermarket ( I assume?) fuel pump/ sender unit again? Or corrosion issues since your original was corroded. Did you check the wiring connectors for corrosion ?

 

[06Escalade]

BMW and Ford owners have a tank float problem and claim polyetheramine (PEA) can fix a sticky float. That chemical can be found in techron concentrat plus fuel system cleaner (Walmart). a couple of bottles in a full tank is worth a try.

 

[01ssreda4]

I replaced mine with ACDelco and it would never go over half on the gauge even when the tank was full. It can be easily modified in the pcm tune, which is what i ended up doing.

 

[Kingx1]

My tank doesn't go all the way to full either, friggin aggravates me so bad!

 

[Devilmk4]

Check the wiring i just changed mine after having my fuel level sensor gone bad on the
Pump. I changed the pump and same thing and checked the wiring haven't had any issues since then about a week now

 

[about20ninj45]

I replaced mine with ACDelco and it would never go over half on the gauge even when the tank was full. It can be easily modified in the pcm tune, which is what i ended up doing.

efi or hpt? where was the setting for that?

 

[01ssreda4]

hptuners, there is a fuel system tab