I have a 2007 pontiac Grand Prix with fuel gauge problems
I'm a HUGE Pontiac/GM fan but their fuel pump sending units are horrible. That's what's wrong with your gas gauge. Shop around a bit and you might find just the sending unit separate from the pump, if you want to go the cheaper route. I'm pretty sure NAPA sells them that way. If your G/P has around 100,000 miles or more I'd replace the fuel pump as well.
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