On my 2000 Pontiac Bonneville ssei, the gas gauge works until it gets to half a tank of gas, then it jumps everywhere when i press on the brakes or even touch the gas pedal. And when i shut off the engine and only turn on the ac. It reads right amount of gas, but when i turn over the engine it jumps everywhere. I was wondering what the problem is and how it can be fixed. Thank you

Sounds like your sending unit is going bad. The sending unit is located on the pump assembly in the tank. It'* not that difficult to get to and you don't have to drop your tank to fix it. The access panel for the fuel tank is in the trunk. Pull up the floor and you can see it on the passenger side.

Here'* a link to the techinfo area on a low cost fix for this.

https://www.gmforum.com/t281507/

I've done it myself and overall it'* a 20-30 minute job. Very easy.

Thank you, for all your guys help. This being my first car, and wanting to know the cheapest way to fix it. Thank you

add this to the to do list with the oil press sensor lol....