Erratic fuel gauge

[akaPedro]

Not working well. Noticed after a right-to-the-top fill up last week.
Gauge reads full while traveling 200-300 miles. At rest it drops to 3/4 full. This is a 2003 National Dolphin LX6355, W22, 8.1L engine. Not an Actia dash, don't know the mfr.

Is there a way to diagnose with a code reader and possibly fix without going into the fuel tank and replacing the sender/float ?

Thanks for listening

[jodeb720]

my 2003 chevy silverado truck had a similar problem. Gauges one at a time started to fail.

Found a guy on fleabay and for 75.00 he fixed it up and shipped it back to me.
NO fuss, no muss.

[monkey44]

If it's an 8.1, probably a GM ... if so, dash panel might need replacement - cost about $400 ... had that happen to my 2003 in 2008, and that was the issue. GM knew it, but claimed out of warrantee - and lots of GM dash indicators failed in several years production around that time. Some failure of switching relays. Had new dash panel installed, that fixed it. Although several of my gauges failed, not just fuel gauge, but they failed one by one, not all at once. A little puzzling at the time.

[akaPedro]

Thanks....had not thought of that. I am an automotive/handyman DUNCE. Guess a rubber mallet and not a regular hammer ?

TIA

[jdc1]

Now it's stuck at the top. If you could get a hammer in there and bang around, it might loosen it up enough to drop. I'm not going to tell you why they say not to top the gas off. I think you know what could happen now. We all do it, until that happens.