At -40* ambient temp, my M1009, after 15 minutes of idling (heat blowing warm), throws out enough white smoke (slightly bluer than gasser smoke - which looks almost grey next to her, If I sound nuts park a good running gasser and diesel side-by-side out in the cold - you'll see what I mean) to make it hard to see the vehicle behind me. After about a 20 minute drive, she barely smokes at all. In the summer, no smoke ever except the first 5 seconds after a cold start. She's got 81,000 miles on her, starts easy and runs very well. Consumes a tiny bit of oil but it's because of a leak, not burning. I wouldn't worry about it.