My 2000 MC ss has a bouncy gas gage. When i get going it says im around 3qrter-full tank of gas when i know for a fact its not. But when i first start the car the gage seems to show closer to the actually amount in the tank. And ideas?

 

Fuel Sending Unit went bad. Not a difficult fix, we have it in our how-to section. Don't need to replace the whole pump just the sensor