Basically, I bought a used 2000 Legacy Sedan. It needed a few fluids changed, basic service, like a 30k or a 60k (the 30k apparently was skipped or missed, the car now has 50k on it). Well, I took it to a shop, and had the guy do it. Today, I picked it up, and noticed driving it home, it had NO POWER at all. It was idling rough, and the CEL was flashing a misfire code at me. I remembered back to my old Legacy L wagon and when I pulled the #3 plug wire while it was running. I called the guy at the shop and told him it was running on 3 cylinders, and he asked me to drive it back.
He found that the #3 plug wire had been bent just a little, and because of that, it wouldn't go into place again. He straightened it, and we were off in less than 5 minutes.
Ever had anything like this happen? Just kinda randomly messing around, then finding out that you learned something that came in handy later...