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The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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

Discussion summary

YOUR RESEARCHThe CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Leading reported evidence

Check before the decision was made

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

The O2 connections were checked before the decision was made to replace all four sensors, so the code itself doesn't make sense to me.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Read full discussion summary

Leading evidence: 'Check before the decision was made' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check before the decision was made' (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 4 other evidence results

Replace four 02's at 100k miles

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

Went ahead and replaced all four 02's at 100K miles.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace headers

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

Replaced the headers after finding hairline cracks at joints.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Check o2 sensor wiring and connections

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

Check all the o2 sensor wiring and connections.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace four sensors

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 · Original poster

The O2 connections were checked before the decision was made to replace all four sensors, so the code itself doesn't make sense to me.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Frequently discussed actions (8)

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

Check before the decision was made

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

The O2 connections were checked before the decision was made to replace all four sensors, so the code itself doesn't make sense to me.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Check o2 sensor wiring and connections

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

Check all the o2 sensor wiring and connections.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace four 02's at 100k miles

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

Went ahead and replaced all four 02's at 100K miles.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace four sensors

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

The O2 connections were checked before the decision was made to replace all four sensors, so the code itself doesn't make sense to me.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace headers

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

Replaced the headers after finding hairline cracks at joints.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace maf, codes came back

No successful repair reported for this finding.

0
Reported fixes
1
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that report an unsuccessful attempt
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.

Unsuccessful attempt · Original poster

Replaced the MAF, codes came back.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace o2 sensor left

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

Then change the o2 sensor left to right and right to left.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace upstream o2 a long time ago

No successful repair reported for this finding.

0
Reported fixes
1
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that report an unsuccessful attempt
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.

Unsuccessful attempt · Original poster

First came up before I replaced the upstream O2 a long time ago. Codes came back.

The CEL that won't die - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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.

  • 986Forum: 1 discussions

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

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

Outcome without a verified action link

Codes came back.

No unique explicit quoted action; no causal link assigned

Generation: 20261027T064914Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

CEL 1276 (fuel metering control) and 0153 (bank 2 sensor 1 ckt slow response). First came up before I replaced the upstream O2 a long time ago. Codes came back. Replaced the MAF, codes came back. My mechanic checks with Autologic thing, zilch. Replaced the headers after finding hairline cracks at joints. Went ahead and replaced all four 02's at 100K miles. (cough EXPENSIVE)... Codes came back. I clear the codes with the scanner, hit a dip in the road on the highway, CEL comes on. Frayed wiring? This has been going forever...

POST 3 / ORIGINAL POSTEROriginal post

Aftermarket. But I was getting this same CEL well before I ditched the stock units.

POST 4Original post

Throwing parts at a car tp fix never works The code you have does not indicate a bad MAF sensor ! And the codes come in an ordee for a reason, usually the main problem is the first cause, and the other are caused by this problem. Go to a good garage and have them diagnose it. Edit: I've just checked, and the problem for P1276 is "signal delay time for oxygen sensor ageing, bank2, above or below limits". So Check all the o2 sensor wiring and connections. Then change the o2 sensor left to right and right to left. Then erase the codes. When the codes come back, if the code is still P1276, then it comes from somewhere else, can be an exhaust leak at the head, or a leak anywhere but in the intake that leads to more air in the exhaust. If it comes back as P1275, then the O2 sensor might be the problem, wire, connection, oxydation... Check it.

POST 5 / ORIGINAL POSTEROriginal post

^Except for the first 02 sensor (my idea), we did not change those parts because of the CEL itself, they were replaced for other reasons (different CEL codes I can't remember right now). I guess the way I wrote my initial post made it sound like I was replacing parts just to clear the codes, but that wasn't the case. The O2 connections were checked before the decision was made to replace all four sensors, so the code itself doesn't make sense to me. I don't know how exhaustive they were about looking at the wiring in general but they're pretty thorough on these things, particularly the mechanic who did the work. Also, there was a leak, a very bad one on the old aftermarket headers which were badly cracked on both sides, so new aftermarket units went in this year. What I'd like to know is why the CEL seems to be tripped by jarring to the underside of the car.

POST 6Original post

We had constant CEL codes on out Mini Cooper. I chased this by changing O2 sensors and it did not resolve, until I found that the mini originally came with NTK o2 sensors and did not like the new Bosch sensors. Once the NTK were installed, the codes have never come back. Just my .002 to your problem.

POST 7Original post

Look at the wiring from sensors to DME. I suspect a mouse may have chewed his way through a bulkhead pass thru and you have intermittent contact with ground.

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