Again Oil in J-Tube after replacing AOS
 

A few weeks ago I replaced my Oil separator with the new updated version on my 2.5L Boxster with 90k on it (proud daily driver). I also replaced the J-Tube (thanks to Mike Focke!), but afterwards the car was still running bad - black smoke (especially at higher rpm's) and when I stop to accalerate (driving with constant speed) the engine is stuttering. At my service station they replaced the sort of EGR valve (cut-off valve), cause they thought it is a secondary air problem - it didn't changed a thing.
Yesterday I wanted to clean the throttle body and I noticed the new J-Tube from the AOS is full with oil again!!! Does anyone has an idea what's wrong with my car?

I still have engine failure codes from all O2 sensors and a lot of missfires on both banks. I think my entire system runs too lean and that's why the engine get's sometimes too much fuel injected (black smoke). I checked the car for secondary air leakages and already replaced the MAF....

I heard from another member that when they replaced there old AOS, they still have small amounts of oil in the jtube... Are you sure you have the newest AOS with al the new updated j-tubes?

Added: have you checked the compression of the cyclindars?

I am sure I got the latest available updated AOS + J-Tube.
So far I did not checked the compression of the cylinders - what do you think? What should it be?

Just checked my records, it said compression check and oil pressure is ok. :troll: