I had the "mystery no start" issue happen to me three times. The first time was in the middle of nowhere, sun going down, with a dead cell phone...not happy. I was just driving and it died no reason, no nothing...it started up after about an hour...the local dealer couldn't find any error codes and didn't know what was wrong and told me it was a "fluke"...hmmm...yes...I know I'm a woman...but please...a "fluke"??!?!? I no longer go to that dealer. 4 months later, the second time I was in the middle of a really busy intersection and it just died for no reason...and once again would not start until it seemed like it "timed out" or cooled down or something. My NEW dealer checked BCM and found 2 codes for overvoltage and undervoltage and suspected internal filure of BCM-loss of skim which causes the engine to shut down. They replaced the BCM. One month later, the third and last time (knock on wood) I had the problem, I went to leave work and it wouldn't start. The engine was cold which totally contradicted the other two times when the engine was warm. I waited the usual hour and it started. The dealer once again couldn't read any codes but thought there might be an internal failure of the relay control module and ignition switch. The replaced both and I haven't had the issue since. The way they explained it to me was the ignition switch couldn't "detect" the key in the car and would shut down...I don't know...being a woman I just want to be able to rely on my car and not have it break down in the middle of nowhere...I feel pretty confident they fixed the problem. I'm amazed at how many other xfire owners are having the same problem. BUT...it still doesn't make me want to get rid of my car! LOVE IT!