Just got mine today! I filled it up to it clicked off and it was 18.1 gallons. Then drove off and it said a little over 3/4 full on gage. Then drove 27 mile and refueled. I took 1.2 gal then I put in .2 gallons more. Still shows 3/4 full on gage. Any suggestions? PS also got the buzzing noices at 2000 rpm. Only 30 miles on car!