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That is interesting because it does mean you can have green bits in the filter and still everything still works - although it seems your green bits are sealant used in the engine rebuild.
What I find annoying is that with these cases (where an engine may be very close to the point of imploding) there is no engine warning light or codes coming up to indicate this. I guess it is just the same as in a car that has a timing belt failure.
I looked at the tensioner cylinder design and it basically just actuates slightly (in and out) in a barrel with seals designed to stop engine oil getting in (presumably) and is activated by the electrical solenoid to make a mechanical movement to tension or release tension. IMO even with the seals broken it probably would still operate (and like the dreaded IMS bearing, when the seals fail be lubricated by oil not grease)? If the solenoid goes then it wont work and you'd get a code fault? But if the seals break down the engine has no idea and the tensioner barrel, being metal can just continue to function and the system doesn't detect any malfunction (because it opens and closes but is more lubricated or the tolerance is such that the external engine oil has no effect. Is the varioCam tensioner a sealed unit or does it take oil from the engine? Guess the seals are there to maintain the internal pressure of the tensioner and without them the power of the pressure is reduced or limited? So many questions...
The fact that Porsche changed the system on the 2002 facelift version to use the VW Audi one is indicative they decide the new one was better or cheaper.
Also, I wonder whether the varioCam units are the same design on the earlier 911 engines and have they ever failed?
Hartech, (engine builders in UK) said when I spoke to them that the real issue was getting an engine failure by the particles blocking the oil pump feed and that an engine flush or sump removal may be a good idea.
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