Alright, So I've been chasing down an intermittent misfire on #1 which would throw codes and finally found out the culprit after doing every other test in the book, swapping coils, swapping injectors, compression test even smoke tested it with a home made smoke machine... this thing would only miss for 30 seconds on a cold start so I figured maybe it was intake leak and as things heated up it was sealing itself up. So I was about to take the potato into the mechanic this morning thinking I've checked everything I can check and realized now that I have one of those little inexpensive boroscopes I want to pull the plug and check for any liquid on top of the piston (link below if anyone is interested in one). Low and behold I finally found the cause of the miss:

Now I'm glad it looks like oil and not coolant and that the piston is not steam cleaned if you know what I mean. But now I'm thinking I'll start with most inexpensive and least time consuming like the PCV valve and then the valve cover gasket. I've read about it possibly being a valve seal as well so I wanted to get some thoughts on this here on the forum. It looks like a fair amount of oil... do you guys think it could be valve seals and is there a relatively noninvasive way to check for that?
Any pointers and direction would be appreciated. Oh, also a few details: there is no oil in the spark plug well yet it did look like the threads of the plug had a little oil on them but I'm not sure if that could have just been the anti-seize had liquified since I had changed out the plugs about 7 months ago.

Now I'm glad it looks like oil and not coolant and that the piston is not steam cleaned if you know what I mean. But now I'm thinking I'll start with most inexpensive and least time consuming like the PCV valve and then the valve cover gasket. I've read about it possibly being a valve seal as well so I wanted to get some thoughts on this here on the forum. It looks like a fair amount of oil... do you guys think it could be valve seals and is there a relatively noninvasive way to check for that?
Any pointers and direction would be appreciated. Oh, also a few details: there is no oil in the spark plug well yet it did look like the threads of the plug had a little oil on them but I'm not sure if that could have just been the anti-seize had liquified since I had changed out the plugs about 7 months ago.
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