Fuel gauge inaccurate / range indicator inaccurate

[Lechef]

Guage was fine first couple of months that I had it, 2005 1.0. Recently, I've noticed the fuel bars fluctuate when I'm running low, one minute I've got 3 bars, the next the last bar is flashing. The range indicator seems to be off by about 90 miles too many. It's correct when I fill the tank, about 380, however after the first 120 miles it starts to be off. Any ideas?

[bronsin]

I had a range estimator on my motorcycle and it after riding 250 miles the icon began blinking indicating about 5/8 gallon left. Theres 7.5 gallons in the tank and when I filled it, it took exactly 5 gallons.

So much for gauges and the like!

Personally I fill my tank when it half empty so I don't condense water in the gas.