So, I recently did a tune-up. I've heard that you can tell the overall running condition of your engine by looking at the plugs. I'm a novice to this whole tune-up thing (do it yourself) and this is only the second tune-up I've done (first time around I didn't pay attention to plug health). Can anyone with a good trained eye tell me how my engine's doing? 322k miles so far... I have attached pics... Starting from the top, cylinder 1, 2, 3, 4, 5, and last is 6.