I checked the consumption given by the computer and the real consumption. There is a difference of 5%.The computer gives 6.3l/100km (45mpg) and the real consumption is 6.64l/100km (42mpg)http://www.autoweek.nl/verbruik/9265/audi-q3-20-tdi-140pk-2013. On the other hand for the speedthe compuer gives3%more then thereal speed measured by the smartphone GPS.