Gas gauge is not accurate, floats back and forth on 1999 Chevrolet Cavalier

Hi, My gas gauge on the instrument panel does not accurately report the fuel level. In many cases it will lean toward the full mark. Once in a while it will accurately go to the correct level, but then will float back to the full mark or close to it. My fuel pump is working fine. Any suggestions?

by in Cincinnati, OH on August 23, 2010
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3 answers 4 comments
ANSWER by , January 12, 2011
why does my gas gage go back and forth and what will it take to fix it
ANSWER by , August 23, 2010
Chevron has a fuel system additive called Techron Concentrate Plus. The formula with the "Plus" is specifically designed to help with this very common GM problem--it's caused by corrosion on the fuel sending unit in the gas tank. If a couple of tanks with the Techron Concentrate doesn't work, then you are probably out a bundle for the fuel sending unit.
COMMENT by , August 24, 2010
Ok, I will try that. thanks for your quick response.
COMMENT by , January 25, 2011
ya, after a 1/4 , mine likes to float too.
ANSWER by , September 21, 2010
Cheveron is temporary fix if it works at all. You will need to replace the sending unit inside the tank itself to insure trouble free problems again. Oterwise you may be looking for a ride to a gas station on the highway.
COMMENT by , September 22, 2010
Thanks for pointing that out. You can easily monitor your mileage to avoid running out of gas whether the gas gauge works or not.
COMMENT by , November 26, 2010
I replaced the sending unit in my 97 Buick LeSabre and it still reads full all the time. Wish I knew what is causing it.