Porsche Cayman Boxster 987.2 Air Oil Separator Replacement DIY

Porsche Cayman Boxster 987.2 Air Oil Separator Replacement DIY

My 2009 Cayman was idling rougher and getting smokier than usual at startup. Both tell-tale signs of a worn air/oil separator. Here’s how I replaced it in my home garage. While this applies to both Caymans and Boxsters, note that this AOS is an updated design that’s different from the 987.1 units.

I’m not a professional mechanic and this video is just intended to show how I approached this project. Use this information at your own risk. OK, disclaimer over. Be safe and enjoy!



Mircea R says:

Great video. One question, can you check the membrane without damaging the AOS? I had it changed about 4 months ago and was getting a lot less smoke at start-up, but now it seems to be back again (although not quite as much and quite as often) and a lot of vacuum at the oil filling cap with engine running, which make me believe that I'm having an issue again with the AOS. But would like to check the state of the diaphragm before changing it again, just to make sure there's nothing else going wrong. Thanks!

eduki says:

Hi Ian, nice DIY there 😉 I have a question for you… I'm after a Cayman S and can't decide between PDK and manual… Coming from an E46 M3 I don't really want a defective auto transmission, and in general auto trannies when they fail aren't cheap to repair. I know that the PDK is by far better and doesn't has any comparison with the old SMGII, but I'd like to hear about your experience as a long term user… Did you experience any issues with it? Thanks!

Wyloch's Armory says:

Was very very helpful for me today. Thanks.

Marius janse van rensburg says:

Great video. Helped me out quite a bit

Happy Time says:

Good video , will keep this in mind , doesn’t look a too difficult job to do yourself, I’ve got a 3.4 boxster 987.2 dfi engine , I suppose it’s basically the same …

tony9189 says:

Great video!

Jochem R.A. Bakker says:

always nice to see the how-tos. Suggested edit: show the startup before (with smoke and rough idle), and after.

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