Not sure if you're being humoristic, but any car advanced enough to have this IQon technology most probably also has a regular basic in-car computer, and those tend to track mileage by default. You don't even have to key in the numbers.
Not being funny - he actually has a Prius which does give MPG readings, but he finds that it's not that accurate. Just because a car has a fancy in-dash computer doesn't mean that it's any good at keeping track of its own fuel consumption.
