First of all thank you for this comedic well though out walk through!!
My car has a misfire on cylinder 4 ONLY at idle and is making a ticking sound very similar to the sound in the video and I have done everything in the book to fix the misfire so far and I am really thinking it is caused by a failed intake lifter not allowing one of the valves to fully open at idle and the cylinder is fuel knocking.
I noticed when I did my walnut blasting one of the intake runners was bone dry while the other side was oily so to me this was a good indication of that.
I saw posted elsewhere a service bulletin for BMW techs to fix lifter ticks and it called for running the engine at 2000 RPM for periods of time. I am guessing this is supposed to clear out the lifters.
Before I tear into the top end again (already replaced the valve cover) I am going to put some ATF into my oil and do the service bulletin to see if I can't get lucky and 'ungunkify' that sticky lifter and solve my problem.
If not I will be referencing your awesome guide to replace the lifters
