If your engine is running rough and your gages look like this one, it’s time to perform some diagnostics.

by Marc Cook

There you are, cruising serenely above a solid cloud deck in the sunshine. Stronger-than-forecast tailwinds are pushing you right along. ATC is cheerful and cooperative, and your passengers have settled in for the flight. Weather at the destination is perfect and you’ve got enough fuel to land with generous reserves. Music is softly playing through your stereo headset and your engine monitor is showing exactly what you expect. It’s a perfect day to fly your perfect airplane as you wonder at the grandeur of it all. …