2008 Multivan 2.5 tdi oil leak in air inlet before turbo

[Silver Caravelle]

Gday all,
Lately I have been investigating oil pooling and leaking through black plastic elbow join from air inlet to turbo of the Multivan (128kw tdi)

My mechanic has cleaned it up and is inquiring re new seals for this elbow to stop the oil leak onto the under tray to at least slow down the leak for now and monitor. We discussed whether the turbo is leaking oil into the elbow as the route cause.The engine runs great with no performance issues and I skeptical that the turbo is in need of replacement. Has done 149,000k.

I am now thinking it is excess oil coming out of the PVC into the air inlet tube ( that then joins to the black plastic elbow and pools oil there). I have pulled the PCV hose off and there is a reasonable amount of oil residue, more than just blowby mist.

There is also only oil mist in the intercooler pipe side of the turbo which is a great sign of no oil spewing from the turbo outlet.

If the PCV is knackered letting excess oil to blowby from the rock cover, is there way to test this without accessing the rocker cover? I cannot see that it is straight forward to access this and replace the PCV without major surgery to remove the plastic rocker cover and intake manifold.

Thoughts would be greatly appreciated.

Regards,

Scott