Here's a mysterious situation: 2009 with 40K, always garaged, no mechanical engine work ever done on it except routine maintenance. Two days ago my wife told me she heard an odd sound coming from the engine right after the car was started. I heard it for myself yesterday. Upon starting it was an odd noise that sounded like a foreign object might have been stuck onto a belt. After 15-20 seconds the noise disappeared. The car ran and drove fine with no symptoms, but the check engine light came on and stayed on. Today I started the car and there was no noise at all - and the check engine light was OFF. Everything seems normal. The stored code was P0014.