More than likely it was a cylinder misfire. This happened to me just after new years coming back from a ski trip. I stepped on it and the engine light came on. The next day I went on the highway to see if I could repeat it, and I did; this time the engine light stayed on. Had to get all new spark plugs and all 24 valves adjusted. At the same time since I have 96,000km on her I got the timing belt changed; total came to just over $900. It's a big job for them to get all valves adjusted, but I haven't had any problems since.