2013 Mustang GT oil on plugs issue?

[Hazoic]

Hi all, ended up getting this 2013 GT from work at a good deal and expected to fix some issues but new ones keep coming up and this is one where I don't know much. I can follow a manual or video but telling if something is bad isn't my strong suit.
Did an oil change and replaced the spark plugs that (I think) have been in there for well over 80k miles and they had some of the old liquid oil still on the threads:

I know enough to tell the liquid oil still being on the threads isn't good, but google isn't helpful and I'm not friends with anyone who would know so asking about it here. My main confusion comes from if the tubes have individual seals, how do all 8 have oil on them fairly evenly?
Here is poor endoscope image (it's meant for drywall, sorry) of the cylinder related to the top right plug in above picture:

And new plug from the same cylinder. Car had only run for a few minutes, moved maybe 30 feet:


Any help would be greatly appreciated!

 

[diambo4life]

Is the car smoking at all? Are your coil ends wet? Are the coil wells wet?

 

[86GT351]

I would suggest having a professional compression and also leak down test done.

 

[StockishS197]

I wouldn’t worry just yet. If the threads had oil on them to begin with, the new plugs would also get oil on them from the wet threads in the head.

I would perhaps clean the threads the best you can and reseat the new plugs, run them for a while and see how the porcelain looks after some miles to get a sense of how the car is running. If it’s running fine and not consuming a ton of oil, I wouldn’t worry much.

You could also do a leak down to check ring health.

 

[Midlife Crises]

All the plugs nasty. I wonder if the PCV system is interdicting oil to the intake manifold.

 

[Dino Dino Bambino]

Hi all, ended up getting this 2013 GT from work at a good deal and expected to fix some issues but new ones keep coming up and this is one where I don't know much. I can follow a manual or video but telling if something is bad isn't my strong suit.
Did an oil change and replaced the spark plugs that (I think) have been in there for well over 80k miles and they had some of the old liquid oil still on the threads:
View attachment 115502
I know enough to tell the liquid oil still being on the threads isn't good, but google isn't helpful and I'm not friends with anyone who would know so asking about it here. My main confusion comes from if the tubes have individual seals, how do all 8 have oil on them fairly evenly?
Here is poor endoscope image (it's meant for drywall, sorry) of the cylinder related to the top right plug in above picture:
View attachment 115503
And new plug from the same cylinder. Car had only run for a few minutes, moved maybe 30 feet:
View attachment 115504

Any help would be greatly appreciated!

Do yourself a huge favour by installing an oil catch can on the passenger side to trap some of the oil vapours that are scavenged by the vacuum in the intake manifold via the PCV valve from the crankcase. This might be enough to reduce or even eliminate the problem.

 

[86GT351]

Do yourself a huge favour by installing an oil catch can on the passenger side to trap some of the oil vapours that are scavenged by the vacuum in the intake manifold via the PCV valve from the crankcase. This might be enough to reduce or even eliminate the problem.

Very good idea. Shameless post time. I am a long time UPR dealer and can gladly help you out.

 

[Midlife Crises]

I would also ask what oil are you running?

 

[WJBertrand]

Does the firing end of the plug (particularly the ceramic center cone) look oily or very dark, or is it just on the threads? I can't really get a good look at the plug ends in your photo.
If the oil is only on the threads, you probably just have a leaky valve cover letting oil into the spark plug tunnels.
If the firing tips of the plugs are oily or heavily carboned up, that would indicate an oil consumption issue. Could be a worn out engine or a faulty PCV system letting too much oil into the intake. Compare the tips of your plugs to a spark plug chart, many chart examples on the web.