So far, I've seen a few reports on this forum about electrical connectors not being fully connected (not snapped together properly/tightly). My 4.6 Sedan fell into that category; I got the "check engine" light early on. I have an OBD-II reader so I checked it myself (dealer was already closed for the day) and it came back "camshaft position sensor." I looked at hmaservice.com and found where that was...and gave the connector a little push. "Click." It was loose. Drove the car a couple miles, shut it off, restarted it and drove another mile, shut it off again, and started it again - i.e. 2 "driving cycles." Sure enough, the code cleared. Been fine ever since (~5700 miles).
Pop the hood, lift off the plastic engine cover (it just snaps in at 4 places, pull each corner one by one) and look at the wiring. PULL on each connector to see if you can find a loose one, then give it a good PUSH to make sure it's seated. Open & close the gas cap too. Put the engine cover back on - line it up using the oil fill cap opening to get started. Then go for 2 or 3 short drives and see if the check engine light goes out.
As long as the check engine light is not blinking/flashing, it's safe to drive the vehicle - at least that's what my local dealer service manager told me.
By the way, the camshaft sensor connector that was loose on my car was located on the rear of the cylinder head, passenger side.
mike c.