Hi, my new 08 reg auris is having very poor mpg. According to autitrader when i bought the car I should be getting 45mpg average. On a flat motorway which is smooth as it has been resurfaces I am only getting 24mpg at 70mph and 30 at 60mph. Even when I use cruise control i get this poor mpg and it is not my driving style as I am being very light on the accellerator and shifting up and down when the light tells me to. Previously i had a 1.9 cdti diesel 06 reg astra and even when I hammered t