hi all, been getting an odd noise after starting my 2000 996 C4 up. it's only happened a couple of times but definitely doesn't sound right! order of events is... turn key engine starts fine about a second or less passes loudish whirring noise/buzz comes from the back of the car, last 1-2 secs it's quite startling and gives me a bit of a shock when it happens! i'm not mechanically minded but sounds like something spinning, maybe the starter not disengaging - is that possible? or the starter on it's way out? it's only happened on cold starts i think but then i don't really do multiple short journeys so every start's cold! told the indy dealer i bought it off when i took my car in to fix my dodgey lock (if you saw my other post it's officially knackered and is being replaced under warranty) and the mechanic said something about a pump going after start. it definitely isn't a noise a healthy pump would make - maybe this is the culprit? what do you reckon :?
Discussion summary
YOUR RESEARCHStrange noise straight after engine start...
1 matching discussions were examined; no attributable action/outcome evidence was detected. No consensus or repair conclusion is claimed.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Read captured repliesInsufficient extracted evidence does not mean there is no answer in the original discussions.
1 matching discussions · 2 captured posts examined · 0 partial discussions
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.
- 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: 20261026T181445Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
EGR valve? They can give a bit of a whirry buzzy noise when they start to go. The EGR (Exhaust Gas Recirculation) Valve blows warm air onto the Cats during cold starts to reduce emissions. It is a cheap part to buy but unfortunately, according to the OPC a labour intensive one to fit and it is not covered by warranty. It would be worth taking it to the OPC and getting there opinion as it may well be a pump that is covered under the warranty.
This is a source reference. Confirm exact model applicability in the original material.