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Small bolt hole on cat

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7 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHSmall bolt hole on cat

Leading reported evidence

Use similar setup

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 had a guage in my old rally car that used a similar setup to make sure it wasn�t running too lean.
Original post Read captured discussion
Small bolt hole on cat

Frequently discussed work

Run too lean

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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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
I had a guage in my old rally car that used a similar setup to make sure it wasn�t running too lean.
Original post Read captured discussion
Small bolt hole on cat

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Leading evidence: 'Use similar setup' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run too lean' (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.

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1 matching discussions · 7 captured posts examined · 0 partial discussions

Compare 2 other evidence results

Run too lean

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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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
I had a guage in my old rally car that used a similar setup to make sure it wasn�t running too lean.
Original post Read captured discussion
Small bolt hole on cat

Test could be performed

Suggestion or failed attempt

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
That makes sense that the bolt could be removed and some sort of emissions test could be performed.
Original post Read captured discussion
Small bolt hole on cat

Frequently discussed actions (3)

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

Run too lean

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
I had a guage in my old rally car that used a similar setup to make sure it wasn�t running too lean.
Original post Read captured discussion
Small bolt hole on cat

Test could be performed

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
That makes sense that the bolt could be removed and some sort of emissions test could be performed.
Original post Read captured discussion
Small bolt hole on cat

Use similar setup

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 had a guage in my old rally car that used a similar setup to make sure it wasn�t running too lean.
Original post Read captured discussion
Small bolt hole on cat

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.

7 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.

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

Generation: 20261026T155324Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Does anyone know what that small bolt hole that is up stream of the first O2 sensor is for? I need to buy a small bolt to thread into it. My old cat had the bolt but it was so frozen the head broke off.

POST 2Original post

i totally read that "Small Butt Hole On Cat" i was like wait what?

POST 3 / ORIGINAL POSTEROriginal post

Lol, ya that is funny, because I read what you typed and was still thinking about my exhaust and read it "small bolt hole..." I guess our brains try understand what we think we see and not always what is actually there. haha

POST 4Original post

I�ve wondered the same thing. I find it odd that it is included in all production cars, since it would add cost (more parts and labor) to the manufacture of the part. There must be a reason for it. Seems like it would be good for exhaust gas monitoring. I had a guage in my old rally car that used a similar setup to make sure it wasn�t running too lean. I wonder if there is some sort if exhaust gas testing in Porsche�s major markets (TUV regs in DE maybe) that require this capability?

POST 5 / ORIGINAL POSTEROriginal post

That makes sense that the bolt could be removed and some sort of emissions test could be performed.

POST 6Original post

Other than going to the dealer you can just measure the hole diameter and then just go to your local hardware store and buy a few different bolts in that diameter but with different thread pitches. Get them as short as possible and then if needed, cut them.

POST 7 / ORIGINAL POSTEROriginal post

Looks like it is a M8 1.0mm. I had an M8 1.25 but it was clearly the wrong thread pitch.

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