2017 20VTX 410 Monsoon engine tapping noise

[Pilz]

Heard a tapping noise from the engine compartment. A Service Soon warning came up on the dash and threw 2 codes; Emissions/catalyst damaging misfire cylinder and SPN 1328 FMI 31.  This code indicates an issue with cylinder 6.  I started to head back to the dock slowly and the codes then moved from Active to Inactive and the Service Soon went away too. The tapping continued.  I changed oil and added an additive thinking it may be a lifter issue.  I ran it then to see if that would clear the noise.  I had cleared the previous fault codes and did not get a fault code when I ran it for a bit but the tapping noise is still there.  Most noticeable on the starboard side (V Drive) loudest near the lower spark plugs.  I'm fearing a major engine issue.  Any other insight?

 

[oldjeep]

I'd start by pulling #6 plug and looking at it.  

[Pilz]

Plug looked perfect

[Pilz]

As a follow-up and FYI...  oldjeep was on the right track.  It was the plug connectors on 2 cylinders.  I'm amazed that no fault codes came up while running it and performance was not noticeably degraded.

 

[Pilz]

When I put the connectors back on, note that those connectors can easily feel like they have clipped onto the plug but actually don't.  I used a borescope to make sure and twice they were off to the side vs on the plug when reassembling.  <end>