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Missfire & Knocking Noise

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Original source

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHMissfire & Knocking Noise

Reported or suspected cause

rattling, theyre surely related

Reported cause

No successful repair reported for this finding.

1
Identified cause: 0
Suspected cause: 0
Reported fixes

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 report identifying a cause: 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.

Reported cause · Original poster
Problem is the rattling, theyre surely related.
Original post Read captured discussion
Missfire & Knocking Noise

Frequently discussed work

Replace ignition coils

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'm by no means a mechanic, far from it in fact but have you changed the coil packs to the affected cylinders.
Original post Read captured discussion
Missfire & Knocking Noise

Read full discussion summary

Leading evidence: 'rattling, theyre surely related' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'rattling, theyre surely related' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Replace ignition coils' (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 · 3 captured posts examined · 0 partial discussions

Compare 1 other evidence results

Replace ignition coils

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
I'm by no means a mechanic, far from it in fact but have you changed the coil packs to the affected cylinders.
Original post Read captured discussion
Missfire & Knocking Noise

Frequently discussed actions (1)

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

Replace ignition coils

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'm by no means a mechanic, far from it in fact but have you changed the coil packs to the affected cylinders.
Original post Read captured discussion
Missfire & Knocking Noise

Reported and suspected causes (1)

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

rattling, theyre surely related

No successful repair reported for this finding.

1
Identified cause: 0
Suspected cause: 0
Reported fixes

Read evidence and context

Discussions that report identifying a cause: 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.

Reported cause · Original poster
Problem is the rattling, theyre surely related.
Original post Read captured discussion
Missfire & Knocking Noise

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.

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

911uk: 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: 20261026T190023Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi We have a 996 3.4, it has developed an intermitent missfire and a knocking noise from one side of the engine, Fault codes p0300, p0301 and p0303 have come up, which basically just describes a random missfire and missfire in cy1 and cy3. We think it could be hydraulic lifters, but just wanted to ask to see if anybody has experienced this before before we go any further Thanks for any help or advice Thierry

POST 2Original post

I'm by no means a mechanic, far from it in fact but have you changed the coil packs to the affected cylinders.

POST 3 / ORIGINAL POSTEROriginal post

Hi Problem is the rattling, theyre surely related. A bloke we know that deals with porsches say it could be a piston gone

This is a source reference. Confirm exact model applicability in the original material.