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Grinding noise from C4S

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YOUR RESEARCHGrinding noise from C4S

Leading reported evidence

Check by a (very) well known expert prior

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Unsuccessful attempts: 1
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Performed · outcome unconfirmed · Original poster
The car was extensively checked by a (very) well known expert prior to purchase.
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Grinding noise from C4S

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Leading evidence: 'Check by a (very) well known expert prior' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check by a (very) well known expert prior' (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.

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Check by a (very) well known expert prior

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
The car was extensively checked by a (very) well known expert prior to purchase.
Original post Read captured discussion
Grinding noise from C4S

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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

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Generation: 20261027T005001Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Just bought a C4S and have been enjoying the daily commute. Until this morning it performed really well. However, I had noticed that if I went over 85mph there seemed to be a roughness (difficult to describe) and what seemed like more road noise. Anyway this morning there was a discernible 'metallic' noise from the rear when I went above 50. When I parked it up I revved the engine and could not get the noise to repeat so I am assuming it only happens when the car is in motion. Anything occur to you folks? The car was extensively checked by a (very) well known expert prior to purchase. Thanks in advance Ken

POST 2Original post

Is it audible at all at low speeds? A bearing springs to mind, but I'd get it checked out by a good independent specialist soon.

POST 3Original post

Is the noise from one of the wheels ie one side or the other in which case it sounds like wheel bearing symptoms. Or is it fron the engine /gearbox i.e central at the rear. If its ony in motion then wheels/driveshafts/gearbox is most likely. An indie will give you an answer.

POST 4Original post

It could be paranoia. What town are you in? Perhaps one of us is local enough to you to come in the car with you to give an opinion. I personally think the 996 is fairly noisey, it could be all normal.

POST 5 / ORIGINAL POSTEROriginal post

Thanks for the replies, very helpful. This is a really great forum. Really hope it paranoia! To be fair it drove well back from work yesterday. I will keep an ear out and get it to a specialist if it reoccurs. If anyone is willing to give it a look I live in Harpenden, Herts. I imagine the recommended specialist is JZ Machtech - they are about 10 miles away. There is a good story around the day I bought it and I will post this later. Thanks again.

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