SO how many of you regularly check the grounding of your mags? ....and how do you go about it? I pulled a bonehead move in the rental the other day that I found interesting...and turned into a good thing I didn't conscientiously do it, but at shutdown I turned the key to off rather than pulling the mixture...and the engine kept running. It sputtered and stumbled but kept running... I had just a moment of brain fade as I processed the event Once the instructor realized what was happening, so did I. I was kicking myself but realizing the bonehead move was good in this case. I then remembered that way back in the day I had started the habit of doing it at shutdown. I went back and looked at my old checklist for that type (172N) and I had even added it as a step for shut-down, prior to pulling mixture But, what my memory is fuzzy on is how actually did I used to do the check. I recon it was much like a Rod Machado video I just found on the topic where he just momentarily went to off and back to both, just to check for faltering. In this case, the engine would have faltered...but leaving the key in the off position would show the problem. So if you leave the key in off to see if the engine stops.... then if it does just pull the mixture to idle with the engine dead. Would there be anything wrong with that? I think this story also points to an issue I have with checklists, but I suppose that's another thread.