4mulafastech
New member
Playing in the garage and decided to pull a spark plug just to check it out. I have 2006 6.2 MPI's. Funny thing is my 6.2 owners manual states that the plug should be a AC Delco 41-983 and what I found factory installed in the engine is a 41-932. I am going to follow-up with Mercury next week, but searching the internet I found the 41-932 is a hotter plug than the 41-983, and that the 41-932 is no longer available and has been replaced with a 41-993. Spark plug alphabet soup! I am wondering if my manual is just wrong. Either way, both plugs will 'fit' the 6.2, just don't know what heat range is ideal. What plugs are in your 6.2's??