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OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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

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YOUR RESEARCHOBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Leading reported evidence

Replace yes, the fuel filter

Performed · outcome unconfirmed

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
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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 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
Yes, the fuel filter was changed at the same time as the pump.
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Frequently discussed work

Check fuel pressure

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Reported fixes: 0
Unsuccessful attempts: 1
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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 · Original poster
I will check the fuel pressure.
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Read full discussion summary

Leading evidence: 'Replace yes, the fuel filter' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check fuel pressure' (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 · 5 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Check fuel pressure

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
I will check the fuel pressure.
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Check fuel system

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
If the overly lean code still shows, I would then check the fuel system for correct pressure and volume delivery.
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace fuel filter

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
Have you changed the fuel filter on the car?
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace fuel pump

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
I did recently, about 400 miles ago have to replace the fuel pump which failed, Bosch replacement...
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Frequently discussed actions (5)

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

Check fuel pressure

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
I will check the fuel pressure.
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Check fuel system

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
If the overly lean code still shows, I would then check the fuel system for correct pressure and volume delivery.
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace fuel filter

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
Have you changed the fuel filter on the car?
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace fuel pump

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
I did recently, about 400 miles ago have to replace the fuel pump which failed, Bosch replacement...
Original post Read captured discussion
OBDII Fault Code Question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace yes, the fuel filter

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
Yes, the fuel filter was changed at the same time as the pump.
Original post Read captured discussion
OBDII Fault Code Question - 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.

5 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.

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

Generation: 20261026T033439Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I had a CEL come on yesterday during a simple freeway run. Since I do not have a DME but only a OBDII scanner I plugged it in. The errors were P1126 and P1133. I know what the error codes translate to, what I am scratching my head with is why one code, (1126), would say "Oxygen Sensing Adaptation Area 1 (Cylinders 4 - 6) - Rich Threshold", and the other "Aging of Oxygen Sensor Ahead of Catalytic Converter (Cylinders 1 - 3) - Below Lower Limit"? So does this mean that one side of my engine is running lean and the other rich? Or is it simply time to change them? 2001 2.7, 5 speed, 90,000 miles.

POST 2Original post

Quotes source post: 422277

P1126 is an overly lean condition on cylinders 4-6 (air leak, low fuel pressure or volume); P0 133 (note that is not the code you posted) is for an aging O2 sensor ahead of the TWC on the opposite bank (cylinders 1-3). And you do have a DME, but do not have the Durametric software, which I would recommend as "global" OBD II scanners often generate misleading codes on these cars.

POST 3 / ORIGINAL POSTEROriginal post

Thanks JFP, you are correct, that should have read Durametric not DME. And I did post the wrong readout for P1133, it should have been "Oxygen Sensing Adaptation, Lower Load Range, Bank 2 – Below Limit". But what could be the problem? I did recently, about 400 miles ago have to replace the fuel pump which failed, Bosch replacement...

POST 4Original post

Quotes source post: 422392

I would suggest getting the car rescanned with a Porsche specific tool as a starter. If the overly lean code still shows, I would then check the fuel system for correct pressure and volume delivery. Have you changed the fuel filter on the car?

POST 5 / ORIGINAL POSTEROriginal post

Yes, the fuel filter was changed at the same time as the pump. I will check the fuel pressure. However what has not been changed in who knows how many miles is the air filter, and since I live on a ranch with lots of dust I'm sure it's way past it's life. I'm going to give the MAF a good cleaning and order a new air filter and see what happens.

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