I was at the Ford dealer checking to see if they were interested in installing cams and when I left the check engine light came on at 3300 miles and stayed on. Checked all gauges and they were normal so I drove it home. Fuel mileage was still where it should be on the computer readout so I was not concerned about it dumping fuel into the cats and ruining them. I am 1/2 way through my first tank of Premium as I have always ran 87 Octane prior to the tank of Premium. Got out my trusty Innova 3100 OBD2 code scanner and hooked it up and damn if it wouldn't read the code! The thing works on my wifes Honda, but not on the Bullitt (CAN protocol). I decided to disconnect the battery for about 30 min. and reconnected the battery after that time and the check engine light stayed off. I may have detected a slight miss at idle, but other than that no problems found. I will report back if the light comes back on. If it comes on I will have O'Reilly's read it before I take it to Ford. Posting this just for information.