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996 3.6 - smoke from both exhausts. Head scratcher!

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14 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCH996 3.6 - smoke from both exhausts. Head scratcher!

Leading reported evidence

Fill (by about 1l)

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

Oil was slightly over filled (by about 1l) but that not enough to cause issues.

996 3.6 - smoke from both exhausts. Head scratcher!

Performed · outcome unconfirmed

"Oil was slightly over filled (by about 1l) but that not enough to cause issues."

996 3.6 - smoke from both exhausts. Head scratcher!
Frequently discussed work

Check intake manifold deep inside where it branches off

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

When the AOS was replaced, did you check the intake manifold deep inside where it branches off to the 3 cylinders?

996 3.6 - smoke from both exhausts. Head scratcher!
Read full discussion summary

Leading evidence: 'Fill (by about 1l)' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check intake manifold deep inside where it branches off' (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.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

Read captured replies

1 matching discussions · 14 captured posts examined · 0 partial discussions

Compare 3 other evidence results

Replace couple of weeks

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

I had the AOS swapped a couple of weeks, but the problem only briefly improved.

996 3.6 - smoke from both exhausts. Head scratcher!

Replace i used

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I used to have occasional smoking on startup, even after AOS was replaced.

996 3.6 - smoke from both exhausts. Head scratcher!

Check intake manifold deep inside where it branches off

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

When the AOS was replaced, did you check the intake manifold deep inside where it branches off to the 3 cylinders?

996 3.6 - smoke from both exhausts. Head scratcher!
Frequently discussed actions (4)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Check intake manifold deep inside where it branches off

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

When the AOS was replaced, did you check the intake manifold deep inside where it branches off to the 3 cylinders?

996 3.6 - smoke from both exhausts. Head scratcher!

Fill (by about 1l)

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

Oil was slightly over filled (by about 1l) but that not enough to cause issues.

996 3.6 - smoke from both exhausts. Head scratcher!

Performed · outcome unconfirmed

"Oil was slightly over filled (by about 1l) but that not enough to cause issues."

996 3.6 - smoke from both exhausts. Head scratcher!

Replace couple of weeks

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

I had the AOS swapped a couple of weeks, but the problem only briefly improved.

996 3.6 - smoke from both exhausts. Head scratcher!

Replace i used

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I used to have occasional smoking on startup, even after AOS was replaced.

996 3.6 - smoke from both exhausts. Head scratcher!
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

14 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

1 acknowledgements have no verified action link; they do not establish a repair result.

Outcome without a verified action link

^^been there & solved the issue by draining a bit of oil & keeping it near the halfway mark.

No unique explicit quoted action; no causal link assigned

Generation: 20261027T154520Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi all I have a 2003 3.6 C2 - recently started smoking from both exhausts on start-up. After a few minutes the oil burns off and all is fine. I had the AOS swapped a couple of weeks, but the problem only briefly improved. I've just had leak down/pressure tests done plus a scope into every bore. The cylinder integrity is excellent and there's no sign of any wear to the bores. Everything points to it being a faulty AOS but the one fitted a couple of weeks ago was a genuine new Porsche part. There's also not quite as much oil build-up in the inlet manifold as might be expected. We are scratching our heads as to whether it could be some other element of the crankcase 'rebreathing' system. Given that: - oil is definitely reaching the combustion chambers on both sides - there is zero sign of integrity issues in the cylinders or head Is there anything else it could be other than the new AOS? Thanks in advance Ian

POST 3Original post

Yes, put a manometer on the oil filler cap to measure the crankcase vacuum at idle, fully warmed up. You should get 4~5 inches of water. If you get 8" or more, most likely your AOS is bad and yes, a brand new AOS can be DOA. Happened to me. When the AOS was replaced, did you check the intake manifold deep inside where it branches off to the 3 cylinders? That flat area can hold 1/2qt of oil!

POST 4 / ORIGINAL POSTEROriginal post

No - the oil hasn't been overfilled (actually hasn't needed topping up since the last service). The car is actually with my local specialist, but I'll make the suggestion!

POST 5Original post

When i had my 3.4 rebuilt, I had a new AOS put on. It failed immediately and had to have another on put on. I had the second one put on at the dealer. I asked of there was a problem with the engine that caused the second to fail and the response was no - just got a bad one. Put 30K miles on after that without a problem.

POST 6Original post

Quotes source post: 14055218

Nothing pi$$es off a mechanic more than when the owner comes in with a list of "suggestions" they dug up from the interwebs! Let him/her do their job.

POST 7Original post

Quotes source post: 14055889

**** pissing the mechanic off I say. Better for him to be pissed off because he was never told in the first place. Some 'so called mechanics' need to be told and pissed off anyway.

POST 8 / ORIGINAL POSTEROriginal post

AOS has been blanked off, still minor smoking from both pipes Oil was slightly over filled (by about 1l) but that not enough to cause issues. Leak test is next to eliminate ovalled bores.

POST 9Original post

"Oil was slightly over filled (by about 1l) but that not enough to cause issues." I think you may want to rethink this. I used to have occasional smoking on startup, even after AOS was replaced. I always maintained my oil level at the full mark, but after reading on here it should be about halfway on the stick, I started using that as a guide a no more smoking at startup.

POST 10Original post

^ Great advice. 1L is gross overfill considering between min and max is only 1.25L.

POST 11Original post

Quotes source post: 14057310

The car is at the local specialist, he doesn't need to be told what to do if he is a 996 specialist. If he does, take the car to someone that doesn't need our feedback. Do you bring a list of "suggestions" to your surgeon?

POST 12Original post

My did the same thing until I lowered the oil level down to half way down the dipstick. And then it took a few weeks to 'burn off' the rest before it stopped smoking.

POST 13Original post

Quotes source post: 14057736

this kinda made me laugh many years ago lying on a stretcher waiting for my number the doctor gets ready to give me an injection and i ask/suggest he put it in the IV T line . With a "hey thats a good idea " look he did..............i told him that i thought i had enough holes in me that day.

POST 14Original post

Quotes source posts: 14057442, 14057694

^^been there & solved the issue by draining a bit of oil & keeping it near the halfway mark. +1, plus it's the cheapest possible solution!

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