Gas problem?

[G_Rider]

When I first got my car of course i got on it a bit , and got about 270 Miles (with one bar left) before I filled up again. Now i've been taking it easy to see what I can get out of it and am almost at half a tank and have about 135 miles on it . So Im getting about the same as I was getting on it. It's a 20 gallon tank right? some how im getting about 15mpg out of it and 85% of my driving is highway. Any advice appreciated.

[Q45tech]

Don't trust the gas gauge fill log drive refill log drive refill log calculate the exact amount. Eventually you will get an idea of what each increment means.

Warning occasionally bad gasoline [high sulfur] can affect the calibration of fuel level sensor plus the fuel pump housing is COOLED by the gasoline so years of running on empty can cause extra wear which problay won't show up until after the warranty expires