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THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHAOS replace
Leading reported evidence
Check any leaks and address them at the same time
Suggestion or failed attempt
No successful repair reported for this finding.
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1
Discussions
Read evidence and context
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Suggestion
I was also able to check for any leaks and address them at the same time.
Leading evidence: 'Check any leaks and address them at the same time' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check any leaks and address them at the same time' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion
It was also a good time to clean the engine, which will help with any future leak identification.
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Suggestion
I will give you a slightly different perspective on going about replacing the AOS on an engine.
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Suggestion
Granted, both of the times were on project cars, that needed to have an engine swap done anyway, but I was sooooo glad that the engine was out to replace the AOS and even associated hoses.
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14 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Pelican Parts: 1 discussions
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Generation: 20261027T035758Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi Barry - take a look at the link below to a link from our site's DIY tech articles on the procedure. Please let us know if you have any questions.
Porsche 911 Air Oil Separator Replacement - 996 (1998-2005) - 997 (2005-2012) - Pelican Parts Technical Article
Thanks Dmitry, I did scan over but not read all the article. I'm busy pouring time and $ into a remodel. Knowing the hrs it takes to do the AOS tells me what to budget for that too. I could do it myself, but time won't allow.
Barry
I will give you a slightly different perspective on going about replacing the AOS on an engine. I have done it twice, on two of the 996's I have owned. Granted, both of the times were on project cars, that needed to have an engine swap done anyway, but I was sooooo glad that the engine was out to replace the AOS and even associated hoses. While the engine was out, not only did I address the AOS, but I also was able to easily replace the water pump, thermostat, spark plugs, starter, misc sensors, alternator, belt, RMS, and the coolant reservoir. Had either of them been a 6 speed, I would have done the clutch at the same time. I was also able to check for any leaks and address them at the same time. It was also a good time to clean the engine, which will help with any future leak identification.
If you aren't worried about all those other items I mentioned, or if the car has low enough miles that it isn't an issue, then just address the AOS.
I guess what I am saying, is that if the AOS is bad, the car might have enough miles on it to just drop the engine, and make sure you can address as much of the stuff at once, without having to pay for duplicate labor and have peace of mind knowing that it is ready to rock for another 50,000 to 100,000 with those items changed.
I also realize that I saved a ton on labor costs doing it myself, and that allows me the flexibility to buy my own parts and take my time. A luxury not everyone has.
I don't think I can do this in 4 hours with the engine in a car for a 996 and I have dropped 20 911 engines in all years. This is not my first rodeo. The access to the AOS at the left hand front side is way too severe. With the gearbox out of the car, maybe. With the engine out, it is a much more manageable job.
Bronco answers my 2nd & 3rd question, thanks. The time it takes will be relative amongst the many good Porsche shops around here.
My initial question was because of milkshake sludge in the oil filler - thinking a failing AOS can cause it. So there's another question, what causes the sludge?
Last weekend I did the vacuum test side by side with a 2003 C4S with a known good AOS, both were sucking similar and were relatively easy to remove.
If you have a Tip and not stick then it's a whole other animal to gain complete access to the OS, last week were pulled the motor in order to gain full access which also allowed us to find and fix a couple of broken vacuum lines that aided in clearing a check engine light.
To drop the motor and change it is around $800 in labor plus around $150/parts
