You said the car sat for 2 years. It could be it's filled up with algae. It's my understanding that stuff will take up some space. Get rid of that so you have a clean tank to start with.

I get about 30 mpg city/hwy combined in metro Atlanta, 28 just city with no a/c, 26 with a/c, and 36 mpg on just hwy miles. So on combined when I'm getting 30 mpg, from full tank to just before running out, I get 465 miles, just guessing I have another 1/2 gallon left at that point, but who wants to chance it, right? So if I really wanted to push it by topping it off on fill up (which I don't do), and running it til it's juuuuust about to run out of fuel, yes, I think I could get 500 miles.

If your fuel gauge is not working right, they're easy to fix, see my post on the DIY forum.

Jeff
1991 300d, 105k