I have a similar if not the same problem. I have 36,000 miles. Ill crank it sometimes 3 times especially if I had my AC turned on previously. Then it will make that grinding noise while it is off as if I had turned the key to start when it was already on. I have been thinking it is a spark issue.

 

Same issue here I believe. Happened about 3 times in the month that I've owned the car. Usually after a short trip (5ish minutes) I would attempt to fire it back up and it would crank for a few seconds and not fire up. I'd wait a few seconds and then do it again and give it some gas while cranking and it turns on. Idles low for a few seconds then all is good again.

Only service engine code I've had is P0442 twice, evap emission leak if I remember correctly.