Hi Guys. Just wanted to know generally how accurate the BMW OBC is compared to actual results especially with fuel consumption. On my car I did a test comparing the OBC to actual results. Filled up the tank, reset the odometer and did 300km. Went back to the garage, filled up again and calculated the consumption. The OBC showed 15.1 km per litre and the actual result was 15 km per litre which was 90% highway with no traffic. Im amazed at how accurate it was. I know from previous BMW's that they do vary, sometimes up or down.