I have filled my vehicle(H2 04) at least three times since I got it last week adn it reads full always right before the full almost at 3/4 but I know its full cause I wait for teh click then add a little more. Also my low gas light does not come on, i was in the red with the needle and no light, what could be the problem?

 

Sounds like the guage or the sender is the problem, I have seen the guages fail many times. If you know someone with a same year hummer just switch out the cluster adn see if it fixes the problem. Easy to do the just plug right in, 15 min job.

 

oh ok thanks, if it is the sender how much is the repair, I know when I first start up the low light comes on but thats the only time I have seen it come on.

 

I have a 2005 Hummer H2 that I just picked up as a back up vehicle and I am working through some mechanic issues. I am having the exact same problem with the fuel gauge as you - everything else on the dash seems to be working fine but the fuel gauge needle literally moves back and forth, from low fuel to 1/2 tank, to 1/4 tank, and sometimes back up to 3/4 if I just filled it, and that's with driving on a pretty flat and even road, not that many bumps and divots to jostle the gauge that much.

I'm just wondering (12 years later it seems) - if you ever found the problem with yours and what you did to change or correct it. Is this just the sendor that needs replacing?

 

2023-2009=14

 

you probably need to replace the gauge servo motors in the dash cluster. very common issue on gm vehicles. symptoms is erratic or non working gauges

 

as bronxteck mentioned the problem usually is the steppers.

If you have access to a good diagnostic tool, you can read the fuel level, you'd then know if it's the stepper or the sender.

If you want in depth information on the fuel sender, search for "H2 Fuel Pump Deep Dive" on YT, it pretty much explains everything to do with that side.