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Do post cat O2s affect fuel mixture?

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YOUR RESEARCHDo post cat O2s affect fuel mixture?

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Adjust mixture

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Suggestion · Original poster
Another person said that it does use the secondary O2s to adjust the mixture.
Original post Read captured discussion
Do post cat O2s affect fuel mixture?

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Leading evidence: 'Adjust mixture' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Adjust mixture' (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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Use secondary o2s

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Suggestion · Original poster
Another person said that it does use the secondary O2s to adjust the mixture.
Original post Read captured discussion
Do post cat O2s affect fuel mixture?

Frequently discussed actions (2)

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Adjust mixture

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Reported fixes: 0
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Suggestion · Original poster
Another person said that it does use the secondary O2s to adjust the mixture.
Original post Read captured discussion
Do post cat O2s affect fuel mixture?

Use secondary o2s

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
Another person said that it does use the secondary O2s to adjust the mixture.
Original post Read captured discussion
Do post cat O2s affect fuel mixture?

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

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POST 1 / ORIGINAL POSTEROriginal post

Basically I've heard conflicting information for the 996 turbo. Some said the post cat O2s are only there to let the computer know that the cats are working and don't affect fuel calcs in the ecu. Another person said that it does use the secondary O2s to adjust the mixture. Can anyone confirm the truth? Also I'm pretty sure the secondary are narrowband and the fronts are wide, can anyone confirm this also. Thank you in advance.

POST 2Original post

No if everything emission is working as designed. If not (e.g., cat efficiency drops), the post cat reading will also impact the fuel mixture trying to compensate. Macster will chime in any time now...

POST 3 / ORIGINAL POSTEROriginal post

ok thanks

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