AOS (Air Oil Separator) replacement

[jhasti]

AOS (Air Oil Separator) replacement

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I have a 2005 Carrera S with 68,000 miles. I recently started having problems with a large white cloud appearing only at start-up and some poor throttle response at low rpms. I had also noticed for the last few months that the oil consumption seemed a faster than usual for my car. After a little reading I found that it might be due to the AOS. My Durametric program was giving some RKAT and misfire codes, but the check engine light (CEL) was not on - of course, after I checked the codes, the

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• Author
  jhasti
• Category
  Carrera (997-1) - Common Fixes and Repairs
• Submitted
  08/29/2010 12:09 PM

 

[Mike0808]

Hi guys. Have ascertained that my aos is shot (squealing like a pig but no smoke as yet) ,have sourced part and the man to fix but was wondering if o.k to drive short dist (10 miles) or no. Thanks

[JFP in PA]

Hi guys. Have ascertained that my aos is shot (squealing like a pig but no smoke as yet) ,have sourced part and the man to fix but was wondering if o.k to drive short dist (10 miles) or no. Thanks

You a significant risk running an engine with a failing AOS on it, if it fails catastrophically, you could hydraulic lock the engine and kill it. Flatbed time...........

[Mike0808]

Hey great advice thankyou,will organise flatbed today,one more stupid question ... I had driven it with the squeal thinking pulley/belt prior to me diagnosing aos however the cel light come on ! Is this what you might expect or have i caused further problems for myself ! Thanks in advance

[JFP in PA]

Hey great advice thankyou,will organise flatbed today,one more stupid question ... I had driven it with the squeal thinking pulley/belt prior to me diagnosing aos however the cel light come on ! Is this what you might expect or have i caused further problems for myself ! Thanks in advance

You are probably OK at this juncture, the squeal is a major vacuum leak in the AOS, the CEL is probably for an overly lean condition caused by the vacuum leak. The big problems happen when the AOS inhales a large amount of liquid oil, which the engine cannot compress and metal starts bending, or worse.

[mlv_250]

I have a 2007 997.1 Tip. Started to replace AOS but can't seem to locate it. I've remove both AC unit and Alternator but don't see it. where else to look? Thanks.