My engine light came on during my trip back from Moab and the Ft Worth dealership advised that as long as its not flashing, the car is okay to drive. Just check it for the type of stuff you have already mentioned (they suggested the gas cap first thing). If it keeps coming back on, you haven't found what's causing it and if it starts flashing, you are not supposed to drive it. Get it to a dealership immediately (they suggested towing it if its at that point).

I think mine was oil related because when I filled it up with oil, the light went off and hasn't come back on.