coil pack question

[sxg6]

I have a 2009 Subaru legacy with around 230k. It still has the oem coil pack installed, and I noticed something weird inside one of the holes.

If you look inside, there are some dark marks that I can't remove with cleaning.
-Do you think those marks affect the operation of that cylinder, or is there enough exposed metal to make up for it?
-The plastic area around that cylinder has started to turn white a little, too much heat?

The oem spark plug wires click into the oem coil to let you know they're secure, but this one particular cylinder has always been a bit troublesome, the wire doesn't click in the same way as the other ones do. I should also mention the metal part of the spark plug wire had a little bit of white corrosion on it when I pulled it out. Sort of hard to clean the metal since I couldn't pull back the boot much, but I was able to get it clean for the most part.

I don't have any misfires, and when I check the resistance between coils as instructed by the factory service manual, everything checks out fine. The plastic looks weird, but there are no actual cracks that I can catch my fingernail on.

I'm guessing the the connection between the wire and the coil pack was poor for that cylinder? I don't know much about this stuff, so I appreciate any thoughts.

*Edit: Sorry for the size of the pictures, I thought they'd show up as thumbnails.

 

[Linctex]

Definitely some arc damage happening there.

 

[frankbee3]

My wife's 2008 Outback had the #2 cylinder position on the coil breakdown and split the coil tower where the spark plug wire plugs in. I replaced the coil and spark plug wires and used dielectric grease hoping it would help.

 

[mk378]

Likely the end of the wire is badly burnt and never going to make a good contact. At 10 years you're due for new wires anyway. Replace the coil too to be sure it doesn't happen again.

 

[eljefino]

And replace the coil and wires simultaneously. A carbon track on one is like an STD-- it'll spread.