Porsche Club GB

Engine knock

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHEngine knock

Reported or suspected cause

lazy tappet

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 it isn't a heavy knock, and you have good oil pressure, I would suspect a lazy tappet.
Original post Read captured discussion
Engine knock

Frequently discussed work

Replace try a 5w-40 oil (if you aren't

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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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
I wouldn't worry, but next time you get an oil change, try a 5W-40 oil (if you aren't already using one).
Original post Read captured discussion
Engine knock

Read full discussion summary

Leading evidence: 'lazy tappet' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'lazy tappet' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Replace try a 5w-40 oil (if you aren't' (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 · 6 captured posts examined · 0 partial discussions

Compare 2 other evidence results

Replace try a 5w-40 oil (if you aren't

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
I wouldn't worry, but next time you get an oil change, try a 5W-40 oil (if you aren't already using one).
Original post Read captured discussion
Engine knock

Use doesn't help

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
It should sound more like a ticking than a knocking sound and in which case it could to be the tappets, I have always experienced this, and had new ones fitted and still the same, lack of use doesn't help.
Original post Read captured discussion
Engine knock

Frequently discussed actions (2)

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

Replace try a 5w-40 oil (if you aren't

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
I wouldn't worry, but next time you get an oil change, try a 5W-40 oil (if you aren't already using one).
Original post Read captured discussion
Engine knock

Use doesn't help

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
It should sound more like a ticking than a knocking sound and in which case it could to be the tappets, I have always experienced this, and had new ones fitted and still the same, lack of use doesn't help.
Original post Read captured discussion
Engine knock

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.

lazy tappet

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 it isn't a heavy knock, and you have good oil pressure, I would suspect a lazy tappet.
Original post Read captured discussion
Engine knock

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.

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

Porsche Club GB: 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: 20261026T161109Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

When starting car up from cold, engine knocks for about 20 seconds any ideas guys? Car milage is 40,000, when warmed up knock goes. Car is only used at weekends, and sunny days. Please put my mind at rest!!! Engine is 3.4cc.

POST 2Original post

If it isn't a heavy knock, and you have good oil pressure, I would suspect a lazy tappet. They sometimes take a while to pump up with oil, especially after a week's inactivity. I wouldn't worry, but next time you get an oil change, try a 5W-40 oil (if you aren't already using one).

POST 3 / ORIGINAL POSTEROriginal post

Thanks Richard, oil pressure is spot on, using 5/40 already, sounds more like a piston knock, rather than tappet.

POST 4Original post

This is very common on start-up, if your piston was knocking it would be quite serious. [ ] If the car stands still for more than 4 weeks for example it sounds like the whole thing is coming apart when you start it, my heart stopped beating the first time I heard it...

POST 5 / ORIGINAL POSTEROriginal post

Thanks Alex thats put my mind at rest

POST 6Original post

It should sound more like a ticking than a knocking sound and in which case it could to be the tappets, I have always experienced this, and had new ones fitted and still the same, lack of use doesn't help. Cheers Phil

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