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Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHWhere do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Leading reported evidence

Clean (and tried a replacement)

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
- MAF cleaned (and tried a replacement).
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Frequently discussed work

Check deposits

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 have not dropped the oil/filter to check for deposits.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Read full discussion summary

Leading evidence: 'Clean (and tried a replacement)' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check deposits' (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.

Read captured replies

1 matching discussions · 2 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Replace by the previous owner

Performed · outcome unconfirmed

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
- Sparks and coil packs are new and only just changed by the previous owner.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Smoke-test now and no leaks

Performed · outcome unconfirmed

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
Smoke tested now and no leaks that I can see, and pressure is held for a short time when the air line is turned off.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Check deposits

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 have not dropped the oil/filter to check for deposits.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace oxygen sensors

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 can't get the Oxygen Sensor off to inspect or replace them.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Frequently discussed actions (6)

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

Check deposits

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 have not dropped the oil/filter to check for deposits.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Clean (and tried a replacement)

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
- MAF cleaned (and tried a replacement).
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace by the previous owner

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
- Sparks and coil packs are new and only just changed by the previous owner.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace oxygen 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
I can't get the Oxygen Sensor off to inspect or replace them.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace when

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 don't think this is an issue and the idle changes when disconnected.
Original post Read captured discussion
Where do I look next ... rough idle ... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Smoke-test now and no leaks

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
Smoke tested now and no leaks that I can see, and pressure is held for a short time when the air line is turned off.
Original post Read captured discussion
Where do I look next ... rough idle ... - 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.

2 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: 20261027T033922Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi, I have a project 2000 986 2.7. It has a rough idle and very occasionally throws a misfire on cylinder 6. I have, I think, discounted all the obvious and easy(ish) to discount problems. - Vacuum Leaks It had some. AOS replaced, this was leaking. Oil filler pipes (two pieces) cracked/split. Replaced. Smoke tested now and no leaks that I can see, and pressure is held for a short time when the air line is turned off. - Throttle body cleaned. Was quite clean, but a bit oily due to the AOS failing. Cleaned and reset. - MAF cleaned (and tried a replacement). I don't think this is an issue and the idle changes when disconnected. - Sparks and coil packs are new and only just changed by the previous owner. - Spark tubes changed as I did see some oil leaking. I can't get the Oxygen Sensor off to inspect or replace them. I am getting white smoke after a couple of days of not starting the car, this clears within 10-15 seconds, but I would consider it excessive compared with my other 2003 986. Fuel quality is likely to be non-premium, but I do not think stale. There is a change in idle if I remove the fuel filler cap. Unsure if I have an injector issue, but no errors suggesting so. Will be getting it on the road in a few days and getting some premium fuel and injector cleaner in the tank. I'm not getting any really worrying noises. I have not dropped the oil/filter to check for deposits. I'd appreciate any suggestions on where to look next. I am considering finding an Indy, or going to Porsche, to see if they can get any more useful diagnostics from the car.

POST 2Original post

By “non-premium” fuel do you mean lower octane? I’m curious if that fixes your issue.

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