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Catalytic converter re-coring

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

Discussion summary

YOUR RESEARCHCatalytic converter re-coring

Leading reported evidence

Replace with a new singular part

Suggestion or failed attempt

No successful repair reported for this finding.

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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.

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Suggestion

Makes sense for the location to be moved if both cores are being replaced with a new singular part.

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Catalytic converter re-coring
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Leading evidence: 'Replace with a new singular part' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace with a new singular part' (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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Replace with single larger core

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
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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
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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 · Original poster

Thanks for confirming how the internals look like (two cores), idea is indeed to replace with single larger core.

Original post Read captured discussion
Catalytic converter re-coring
Frequently discussed actions (2)

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

Replace with a new singular part

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

Makes sense for the location to be moved if both cores are being replaced with a new singular part.

Original post Read captured discussion
Catalytic converter re-coring

Replace with single larger core

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 · Original poster

Thanks for confirming how the internals look like (two cores), idea is indeed to replace with single larger core.

Original post Read captured discussion
Catalytic converter re-coring
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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.

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

  • Rennlist: 1 discussions

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Generation: 20261026T174436Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Originally US spec 996.2 C4S M96.03 now living in EU, no CEL/codes Catalytic converter core pieces have come loose and now rattling so I'm thinking to re-core my cats On parts diagram, there are two types of cats: 99611302159 99611302160 (M661 option which stands for stricter emissions?) Parts diagram shows (I belive) normal cats, O2 sensor before and after, yet on my car one of the O2 sensors is directly on top the core itself (M661?) or perhaps between the core elements? My setup can be seen on this picture https://cimg2.ibsrv.net/gimg/rennlis...43a5a93208.jpg Now when looking at https://jmautosports.com/products/fa...-fsfer430oeccr for example, what they have done is plugged the sensor hole and added new one after the cat in "normal" location. Most aftermarket cats on sale also have the normal setup. Before I go and cut mine up, has anyone done this or has any idea if relocating the O2 sensor like this has any ill effects?

POST 2Original post

On my C4S, the downstream O2 is also between the cores. The first (smaller) cores came loose on both while the second (larger) stayed in place. Makes sense for the location to be moved if both cores are being replaced with a new singular part.

POST 3 / ORIGINAL POSTEROriginal post

Thanks for confirming how the internals look like (two cores), idea is indeed to replace with single larger core.

POST 4 / ORIGINAL POSTEROriginal post

Did the re-core, single replacement core element was installed and O2 sensor moved. No issues or CEL

POST 5Original post

$5k! That's ridiculous! Considering you can buy the catalyst itself for basically $100....its a huge Porsche tax!

POST 6 / ORIGINAL POSTEROriginal post

To be clear, I did not do the Fabspeed option. The parts+labor in this part of the world was about 900USD with majority of that being the cores.

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