O2 would be nice if that's it, though that's awfully soon for an O2 sensor to go. Also, there is an emissions warranty on EVERY new vehicle sold, and it's required to be there according to federal law. I do NOT recall the details of what's what, so review your warranty book, but my first thought is that this, as an emissions control performance issue, may be covered by that warranty. Again, check your warranty book to verify.
My own personal guess is that this is still an electrical issue, and maybe or maybe not a hard-part failure as well. Interested to hear how it turns out.