Are there really any AOS issues on the 987.2?

My research seems to suggest that AOS failures on 987.2 and 997.2 cars is a rarity compared to the 987.1 and 997.1 cars. As anyone had one truly fail on their 987.2 car? When I purchased my 2011 Cayman base back in October, I pulled the engine cover and the motor was filthy. Although there was no pooled oil, there was a significant amount of oil residue and in some cases wetness around the oil cooler, MAF and the entire intake assembly, as well as an oil film and some oil droplets in the intake hose and lines that run from the AOS to the intake body. I do not get any smoke on start up and no strange noises like squealing. The AOS is the original to the car as it has a 2010 build date on it. Is the AOS failing or is this just the accumulation of 12 years of oil vapor and residual weeping out of the intake? I am wavering on replacing the AOS (looks easy enough and cheap) but don't want to waste the money if no one has never had one really fail. I'm also left to wonder if the primary cause was overfilling of the crankcase with oil by owners and shops that didn't know better. When I got the car, CPO'd from Porsche Colorado Springs, the oil level was completely full. After 2,500 miles, it dropped to 3/4 and has stayed there for 1,500 miles. This is the level I'll maintain. https://cimg2.ibsrv.net/gimg/********.com-vbulletin/2000x1504/3_02141c99d648d55a8e20df57e3465904403f1d51.jpg

If you're going to keep her, the AOS part cost is a triviality and a decent preventative. Your labor savings make doing it an easy decision even if the source of this soot is something else. I bought mine from FCP Euro , free replacement when it needs another one.

I have 91k on my 2010. I assume it's the original AOS since all the service appears to have been done at dealerships, who won't bother to replace things unless they're broken. I also have no consumption to report, and my indy says everything seems perfectly fine. I agree, I haven't seen any failures on 987.2 either.. but like Boris said, for the low cost and easy replacement, it's probably worth it to just DIY it and be done with it. I mean, if that's really the only preventative we need to do, then why not, you know? I don't know of anything else that really needs to be done (other than plugs based on age, due to seizing)...? EDIT: One thing I have read is to be sure you use an OEM. There are lower cost knockoffs, but I have heard they fail prematurely and often. The FCPEuro way is a good way to get OEM and get it replaceable, just in case!

Sure, the 987.2 AOS can fail, though it seems more reliable than the 987.1 version. There are more common sources of oil on the engine in my experience though, and I'd start with these before replacing the AOS : - The corrugated oil vapor hoses to the AOS (bottom of your picture) can get brittle and crack and leak oil - If you fill the oil to the full line, these engines seem to dump a lot more oil into the intake. Then it runs past the throttle and drips out near the MAF. They seem to do better and consume less oil if you only fill to one bar below full - The two big metal straps attaching the intake to the plenum, if loose, will allow any oil in the intake to drip out onto the top of the heads That engine is pretty filthy and could do with a good cleaning. I'd get a can of Gunk Foamy Engine Brite (or if you want to spend a bit more, P21S Total Auto Wash works amazingly well) and follow the instructions: spray it all over a cold engine, let it sit a bit, and then gently hose off with an open hose. That'll get rid of a lot of the dust, dirt, and oil, and then you can just monitor for leaks from there to see what's going on.

^Thanks. I did clean the motor right after taking that picture back in October 2022. I've had the engine cover off numerous times since then and haven't noticed any seepage, leaks, etc. I did check the intake manifold clamps and they are torqued to spec. The corrugated vacuum tubing is crack free and the o-rings aren't torn and remain flexible. I'll go ahead and replace the AOS and disect the original. My hunch is the previous owners never took off the engine cover and maintained the oil level at 4 bars for nearly 12 years and caused oil weeping from a number of common seepage points . Like you noted, I'll be running the oil level at 3 bars.