2017 160,000 miles Owner said these are original. #3 looks dark. Wetness might be from me first spraying wd40 before removing.
Complaint was little rough start. Engine could be heard cranking a few extra times. Nothing abnormal once started.






Starting was perfect but only for a few days.
Two weeks later I pulled #3 spark plug and here is what I found.
The shine on the threads might be from anti seize. Oil away on other side of crush washer, maybe the valve cover leaking down. Or could it be it leaked inside and traveled past the washer when I flipped the plug.






I put new ignition coils. And a new plug again. This lasted a few days and same problem again. Ruled out it's not coils.
What does this look like, oil on plug or rich mixture?

 

It's oil. With these engines, the spark plugs typically get coated in black soot when running to rich.
In which country is the vehicle operated?

 

Car is in cooler part of California. Always warm but almost never hot.

 

Those plugs definitely needed to be changed at the bare minimum. Does the car have any other issues going on? I would definitely start throwing in a bottle of chevron techron complete fuel cleaner every 3k-7.5k miles.

 

Harder to start. #3 plug is repeatedly black. As I mentioned I already pulled it out two weeks later and it's black.

 

I'm wondering if VCM is playing a part...