But bear in mind that it's a bit pointless giving internet diagnosis for a generic fault light. There are nearly 10 sensors on the engine, a bunch of solenoid valves and other controls, plus associated wiring, so the failure could be of anything.
Get the car on Examiner/witech and find out what it says, having had the light come on more than once will mean there's a good chance it'll be easy to find the fault.