Pontiac Repair: Fuel Gauge Reading, fuel level sensor, gauge reading

Question
I have a 1999 Pontiac Grand Am GT, V6 engine.  The fuel gauge goes to full when I fill up and continues to fall as I use the car, as expected, but when it gets down to 1/4 it starts to go back up.  Any ideas?

Answer
Hi Bob:

You need a fuel level sensor for this car The sensor is part of the gas tank fuel pump assemby. It is serviced sepertaly from the pump. It's a pretty common issue. I can'r remeber if the v6 or the 4 cylinder had a software update for the engine computer for odd fuel gaude geading as well. I'm going to say it was just for the 4 cylinder but I'm not 100% sure. The level sensors go bad in these cars all the time. The additives the refineries put in the gas eats the sensors up. There is an additive that GM sells that is a fuels system treatment/cleaner and level sensor protectant. That should be used about 2X a year and it will help to stop this from happening again. Good luck :0