Mine quit on my right cylinder. I suspected an ignitor. Eventually the dealer replaced both coils and the ignitor. Never did it again.
At first it did it only occasionally, usually after running steady for 20 or more miles. If it gets to be often, you can try swapping the left and right coils. If the problem moves, it's the coil. If the same cylinder cuts out, it's likely the ignitor. I'd try all the other obvious stuff first.
