I've had issues smelling oil outside the vehicle after I drive ever since I purchased my pre-owned 2008 Cayenne Turbo. The dealership has looked at it several times and their latest determination was that the crankcase breather valve was shot. They have replaced it but the breather still appears to have some oil on/in it.

Has anyone else noticed this on their 4.8's? For those who are not familiar with the part, it is the "T" where the two hoses come together on top of the engine (on the side closest to the windshield).

 

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