Just purchased the X5 a little more than a year ago and haven't had issues until recently with the cold weather. Lately it's been in the 30s-40s (F) and the starter engages and turns but it won't start. It doesn't sound like the battery (turns over strong), and I just had it in the shop and there were no fault codes and they couldn't find anything wrong. They checked for moisture in the electronics box and found none. Each time this happens it eventually starts after several attempts. Once running, it almost dies and it takes about 10 seconds for the RPMs to return to normal. It has only 36,000 miles on it and of course the factory warranty just ran out. It gets regular maintenance and I use only premium fuel.
I have an 01 X5 and have never had any major issues. I convinced my girlfriend to get her first BMW but she is now seriously thinking of getting rid of it...anyone have any similar issues?