Thread: Fuel Gauge Reading Inaccurately

I literally just dealt with this with the help of the fellas on here. My grand prix is an 03 3.1 v6 tho. Mine was pegged between 3/4 and full. Replaced sensor, and still didn't show correct fuel level. There is a write up by onlywinged1 if you Google the gas gauge not working, but it's a lot of wire chasing, voltage/resistance testing, and time. I said screw it and will just refill every 400 miles since I'm assuming it wasn't just the fuel level sensor. Your issue might just be that. But I was told to not by the $90 acdelco sensor, but either the Dorman or tech smart brand.

Yeah, I could move the float arm by hand and it would register from empty to full on the gas gauge, but once it was in the tank, no go. Not sure why it would work out of the tank and not in it but I spent too much time on it, got frustrated and said screw it. Maybe I'll get lucky and fill it up and it'll read right lol. Doubt it but whatever.

There's a thread over on Duramax forum about this (or related issue). The rheostat in the sender makes intermittent contact which affects your readings for the fuel level. In the trucks they tend to show empty, but occasionally bounce to the appropriate level before dropping off again. A lot of guys buy the cheaper GM sender and pop rivet the rheostat into the original unit since the diesel-specific sender is outrageously expensive.