I bought my 2005 X5 4.4i about 3 weeks ago. 196k kms. It runs great and nothing wrong other than a few minor fix ups. However, I noticed just after I picked it up a random puff of blue smoke after a stop at a traffic light. It hasn't done it since. Then, about day 4, it started spewing white smoke for about 10 minutes or so. Like, a big cloud of it. I stopped and looked around a bit and it smelled like water vapour not oil. After 10 minutes or so it stopped. It hasn't done it since. I've put about 1500 kms on it since I bought it, including a couple of highway runs and lots of City driving. Thoughts?