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911uk

c2 knocking

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

Discussion summary

YOUR RESEARCHc2 knocking

Leading reported evidence

Use mobil 1 ( will

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

fresh oil 450 miles ago - assume indie used mobil 1 ( will check ).

Original post Read captured discussion
c2 knocking
Frequently discussed work

Check )

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

fresh oil 450 miles ago - assume indie used mobil 1 ( will check ).

Original post Read captured discussion
c2 knocking
Read full discussion summary

Leading evidence: 'Use mobil 1 ( will' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'tappet oil pressure' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check )' (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 · 5 captured posts examined · 0 partial discussions

Compare 3 other evidence results

tappet oil pressure

Suggestion or failed attempt

No successful repair reported for this finding.

0
Identified cause
1
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 suspect 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.

Suspected cause

If you turn the engine off and restart within, say, 30 mins and it doesn't make that noise, it is probably the tappet oil pressure.

Original post Read captured discussion
c2 knocking

Check )

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

fresh oil 450 miles ago - assume indie used mobil 1 ( will check ).

Original post Read captured discussion
c2 knocking

Recommend `heavier` oil

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

any recommended `heavier` oil?

Original post Read captured discussion
c2 knocking
Frequently discussed actions (3)

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

Check )

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

fresh oil 450 miles ago - assume indie used mobil 1 ( will check ).

Original post Read captured discussion
c2 knocking

Recommend `heavier` oil

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

any recommended `heavier` oil?

Original post Read captured discussion
c2 knocking

Use mobil 1 ( will

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

fresh oil 450 miles ago - assume indie used mobil 1 ( will check ).

Original post Read captured discussion
c2 knocking
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.

tappet oil pressure

No successful repair reported for this finding.

0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that suspect 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.

Suspected cause

If you turn the engine off and restart within, say, 30 mins and it doesn't make that noise, it is probably the tappet oil pressure.

Original post Read captured discussion
c2 knocking
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.

  • 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: 20261026T120458Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

hi , 98 c2 tip on start up there is a slight knocking from o/s rear of engine which clears after warm up. oil pressure is fine, car/engine behaves normally. sticking tappets? or something serious to worry about? - shafts/bearings etc. 90k milage, i work on the assumption that if was gonna go, it would have by now! ( glass half full etc) regards ed

POST 2Original post

If this only occurs at cold start-up (ie first thing in the morning), it may be just the oil pressure momentarily building to operate the tappets. If you turn the engine off and restart within, say, 30 mins and it doesn't make that noise, it is probably the tappet oil pressure. Which would be normal.

POST 3Original post

I would start with sum nice fresh oil mate then go from there :thumb:

POST 4Original post

Do you know what kind of oil you have in it? 0W40 or 10W40 For the higher mileages the general opinion seems to be to go for 10W which is slightly thicker when cold.

POST 5 / ORIGINAL POSTEROriginal post

fresh oil 450 miles ago - assume indie used mobil 1 ( will check ). any recommended `heavier` oil? - bearing in mind winter draws on and milage......

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