Sorry to rehash this thread but, My Contour is currently getting 21-23 mpg mixed driving. My Mustang is actually getting the same or better mileage with a heavier car with more cylinders, more power and more torque. Is the efficiency of the Contour that bad? I shift around 3-4k in normal driving with the tour. And I by no means "baby" the Mustang. This sucks. The Contour has a brand new air filter so that is out of the picture. Tire inflation is 2 psi over recommended.
Hell, my Mustang averaged 19 mpg during the Woodward Dream Cruise including bumper to bumper traffic all day, spirited driving and a couple burnouts.