Still learning about my 4500 system. Tracked my gallons used from each tank this week on a few flights to see how accurate my indication was. EFIS said I used 4.3 gallons from left tank but when refueling I was only able to put in 3.3 gallons. EFIS showed I had burned 8.8 gallons from the right tank but When I filled up I was only able to put in 6.08 gallons. It is common for this to be that far off? Is there a way to correct/calibrate my fuel used?