Q: Engine missing, running rough?

About a week ago, while I was driving, the engine suddenly started running very rough, lost some power, and the check engine light, which was already on, started flashing.

Mechanic Q: Engine running rough?

About a week ago, while I was driving, my engine suddenly began running very rough. At the same time, the check engine light, which had already been on, began flashing. I might add that the truck has 217,00 miles, was tuned up about 10,000 miles ago, and has had no major problems to date.