Car wont start, Help

[krasavchik]

Hey guys, i have a 2002 330CI, which i just recently purchased, but it has a problem that even my mechanic has trouble catching. When it is a cold and damp morning, the car wont start. The starter is going without a problem, but the engine doesn't start. But once the sun comes out and the car warms up a bit, it starts without a problem. My mechanic (who specializes in German cars) said we need to catch it and scan it while its doing that, but by the time he usually gets to the shop, the car is already in the sun and starting. I was wondering if any of you have had this problem before and what it was.

Thanks in advanced.