In a previous thread about MPG in the city for short trips, comparing Eco, Normal and Power modes, some people said that mileage would be low for short trips because the car needs time to "warm up". Can anyone confirm whether this is actually true? When I start the car, the engine usually turns on and runs for a minute or two, then turns off. I always thought this process warmed the engine up sufficiently, since it seems to run longer when it's colder. Has anyone tested mileage over time and verified that it's significantly worse for the first N miles?