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Discussion Starter · #1 ·
After taking out the spark plugs and I can see some oil sitting on top of the pistons.

I did compression test and it looked ok to me: 206, 196, 210, 210.

I took off the intake manifold and checked the PCV valve, it looked ok. Also the inlet side valves all looked ok, no oil visible leaking on or past them. No signs of any damage there.

No sign of any oil in the coolant or any coolant in the oil.

What else could it be?
 

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How did you check the pcv? You said that you took the intake manifold off, did you try tipping it upside down? If you dump an excessive amount of oil out then the pcv is still your suspect.

Otherwise, oil creates a pretty good seal around a set of piston rings so if the rings were the culprit, a good compression test can be a false negative.



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Discussion Starter · #3 ·
I took the PCV valve out and checked it, seemed fine. No gunk inside it or in the pipe, the valve moved freely inside when shaking it etc

There was a small amount of oil inside the manifold, but not enough to drip out, just enough to look slightly wet.
 
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