This is as unexplainable as the thermometer on my Suunto watch telling me it's always 89 degrees
The only thing that bothers me is the inability to adjust the temperature and MPG calculation. I can do it on my '11 Outback easily, and it gets perfect temp/MPG readings (at least once it's been driving for 10-15 minutes). I could adjust it on my '03 330Ci as well. I hope there's an easter egg adjustment menu someone hasn't found yet.
Aside from that I leave the temp gauge off and have it on MPG or ODO. I have my S4 to tell me the weather.