the other night when i came back from my dinner break at work i remembered my gas was at 1/4 of a tank. when i left to go home, the gas gauge read that my tank was completely filled. it was even passed the "F" mark. so i drove home, no problem. now this morning, i went to go take it out and i guess it must have dropped. then, i drove over some rail road tracks and the gauge shot up again. i dont know what to do. how do i check for problems like this? could it be the cluster? or something to do with my fuel pump?

 

You know what I would do? I would just fill it with a full tank and drive it around and see if it ever does it again. Could just be a fluke and it needed to be knocked lose by a full tank. It's a shot in the dark but it's the cheapest easiest thing to do. Use your trip odometer as your gas guage for the time being.