Oil on spark plugs

Currently have an issue was having a po172 code, thought I would do a clean up and replace the spark plugs. I haven’t had any codes for running rich anymore, and fuel trims seem to be reading good. I have a po303 now misfire in cylinder 3. Here are some photos of the spark plugs. Spark plug 3 is showing oil on thread worried it could be blow by rings. Did compression test a year or so ago all read 180s.

 

Valve cover leaking into the spark plug boot?

 

I took a look at the seal it looks some what good. It’s really hard to tell cause the top of the spark plug is clean it’s only the threaded parts

 

I was thinking seals too. Replaced mine at about 120K miles. I would expect more fouling on plugs if it was blow by but no experience with that on an auto. You can always clean it all up and recheck it.

 

Really the only way to tell if the spark plug seals are bad is to take the cover off. Depending on mileage once you do that they almost just fall apart. Comes in a kit with the valve/cam cover gaskets etc. You can have someone do it for a pretty penny or save some coin and do it yourself. Gonna be close to $300 for all the parts needed (all oem).

 

Our trucks never get oil on plugs...How many miles because somebody neglected that motor.