My 2009 2.0 TFSi been sitting in the garage un-used for past 3 days. Was out in it today. Outside temp reading -4.5c. After driving about 6 miles along B roads averaging 48mph, water temp gauge was reading about 70c. (normally in 0c or above air temps the gauge reaches 90c within about 4 miles). Stopped at lights it dipped to about 55c. Then after a another 2miles in city traffic it crept up to 90c where it stayed. Never seen this before in my MK5 GTi nor this car last winter. Engine idled as smooth as ever. Coolant level was topped up with 100ml of pink Audi anitfreeze a few months back.