Earlier today I left my '03 Pilot with 224,000 miles running with the ac on while inside a business (girlfriend in car) for about 30 minutes or so and when I came out it had stopped running shortly before I got back. I started it and it ran real rough for a moment and then quit again. The engine warning light was on as well as the VTM-4 light. Temperature gauge showed normal. Gave it a minute and restarted it and it ran rough but quickly got better. Let it idle for a bit and drove away and it was fine. Checked for codes when I got home and it showed misfires on cylinders 1,2,4, and 6 (codes P0301, etc.). I cleared the codes and they haven't come back and I drove the car around for a while and everything was normal. First time anything like this has happened. I've owned the car for a little over a year and haven't checked the spark plugs yet. Does that seem a likely cause? Any suggestions? I did the triple transmission fluid change yesterday since it was pretty much black when I checked it so there may very well be some other maintenance due on it.