pope said:
You have two gas tanks? I only get 290 per tank. Your gauge is definatly f'in broken son!
If you were talking to me, no, my gauge is not broken. Maybe your IS is broken.

The IS does not get horrible mileage on the freeway. I am consistantly getting about 340 or more a tank when the roads aren't busy, mostly highway, but this tank, for example, I am at half a tank and about 140 miles, because I have been in more rush hour traffic than normal. Consumer Reports even shows that the cruising range of the IS is 410 or 420 miles, so it is possible. People drive in very different environments, temperatures, and with very, very different driving styles. Low tire pressure lowers mpg; windows down can cause drag at high speeds; there are many variables. Why are so many people in disbelief just because it hasn't happened to them?! It really depends on the type of traffic I'm in.