@ Old Master, thanks for your very helpful 4 step process. It was easy to understand, and logical. I rearranged the steps ever so slightly simply to do the easiest task first. But the result was the same. I was totally surprised when it turned out to be a spark plug! I've never had a spark plug look so good yet be the culprit! I resolved the problem in less than 15 min with your method.
I was sure it was a fuel injector, and had been putting off the job of replacing it for months. Thanks to you, I just needed a set of spark plugs. The porcelain on one plug had cracked. The gap looked good, and the color was a perfect tan color. All looked good to me. But when I swapped the 1 and 2 plugs, the code followed the spark plug! As I was wiping it clean, I discovered the cracks, and realized my problem. I replaced it, and it purred like a kitten!
Even though this post was 5 years old, your posted advice was still helpful to me.