Hey so I have a Ford F-150 with around 188,000 miles on it with the 4.6L motor. It was getting a misfire so I popped the plugs out and saw oil on the threads of the cylinder 1 plugs. I decided to put em back and take it to a shop as I really didn't know what I was doing and they replaced the plugs and coils. The misfire however has gone away and its been a month since the repair as well and no CELs. Should the oil on the sparkplug just be ignored or is there more to be done? I keep hearing that I may need a valve cover gasket on forums and such but not from any mechanics. Compression tests came back normal however so I ain't worried about worn out piston rings. Just the valve cover gasket I guess. Thanks for your guy's help!
Given what Scotty prescribes, above, it's time to take a look, yourself, and see with your own eyes. I would bto be surprised to see a break in the gasket, or perhaps the gasket has lost elasticity and become hard and brittle. As Scotty demonstrates, replacing the valve cover gasket is a very DIY type of job.
