I know this problem was posed before, but I tried searching with different keywords and couldn't find any pertinent results.

The last time I took apart my dash about a month ago, I brushed against the gas guage and pushed it to empty. When I went to the gas station, I filled up and it reset my guage and it worked fine. Recently, with the warmer weather (not sure if this is a factor), my gas guage now overestimates how much gas I have left. After 100 miles, it'll still be on full, at 150, I'll be at 3/4, and with 2-3 gallons left, it'll register at about 1/3. Is there any way to reset it? If I take it to the dealer (non warrantied), will they charge me up the ass to fix it?

Thanks for reading,
Will