AOS Oil Leak

[Bilmar72]

Hi Everyone,

 

I am intrigued.  Attached is a photograph of an oil leak from the front of the engine of my 2010 Boxster S.  The pics show the front upper and lower oil pan just below the front engine mount when the leak was at its worst.  Of course this is the 3.4 DFI engine, the car is pristine and has only covered 33,000 kms.

 

The history is that the leak was diagnosed as a faulty AOS at the last service a month ago and the AOS was changed.  But the leak persisted, not a lot, occasionally a spot on the garage floor but not always.  Looking from above and from behind the front seats the engine appeared to be completely dry above the upper oil pan.  Also the PDK had become very sluggish and unpredictable when taking off from a standstill but otherwise the car appears to run fine.

 

When I reported back to the dealer they advised that both problems were caused by the AOS.  They said that the new AOS was a faulty part and happily agreed to replace at no cost.  This has now been done and after a hot 250 km run the leak has stopped but there is still some oil residue around the lower pan.  But nothing like in the attached picture.  The dealer advises that this is oil leaking from the intakes left from the bad AOS and that it will clear over time.

 

Miraculously the PDK is back to perfection so I guess the dealer knows his stuff.  But does this make any sense?

[leafdude]

Very interesting that a faulty AOS could cause the PDK to be effected. Anyone know why that’d be the case? Perhaps the faulty AOS causes lower vacuum and the PDK is sensitive to low vacuum?