POST 1 / ORIGINAL POSTEROriginal post
I just noticed today that upon start-up my C4S puffed a cloud of blue smoke... Is this normal, or do I have potential problems? After start-up the smoke went away, and my ehaust tips are clean... Thanks
10 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
Discussion summary
YOUR RESEARCHSmoke on Start-up?
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 · 10 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.
10 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
- Rennlist: 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: 20261026T200546Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
POST 2Original post
Blue Smoke: Blue smoke is caused by engine oil entering the cylinder area and being burned along with the fuel air mixture. As with the white smoke, just a small drop of oil leaking into the cylinder can produce blue smoke out the tailpipe. Blue smoke is more likely in older or higher mileage vehicles than newer cars with fewer miles
POST 3Original post
Boxer engines do that if you do not let them iddle a bit before you shut them off. Especially, if you just stopped after some spirited driving - in that case let it iddle for 2mins before shutting off.
POST 4Original post
Could be valve guides.
POST 5Original post
Did the car sit a while? If so, it could be some leaked oil that got burnt off. Why the internal oil leak is unknown. Monitor your oil level and if it drops, you could be in trouble...
POST 6Original post
I used to have a K75 BMW Motorcycle and if I parked it on the sidestand when it was warm I could clear fields of mosquitoes when I fired it up again! The problem was that a little oil would drain to the valve area and then, as the engine cooled, it would get pulled into the cylinders. Hopefully yours is something like that. Just check how much oil it burns over time. Barry
POST 7Original post
I get this at the track once in a while. It has to do with just where in the stroke the engine stops and where a little oild leaks. If it is just once in a while, I wouldn't worry about it. If it is constant, that may be a problem.
POST 8Original post
Patrick, I've seen this too on 996's driving at the track. Doesn't it have more to do with the fact that it is NOT a dry sump system and that the g froces cause oil starvation during spirited driving?
POST 9Original post
I don't think so. While it is a concern, I don't think it causes the smoke on startup.
POST 10 / ORIGINAL POSTEROriginal post
Thanks ALL...I have been watching this closely since the post, and no reoccurance...strange, but needless to say i'm glad. But I will continue to monitor. As for oil usage, nothing out of the ordinary yet (about a quart in the last 3500) Anyway, appreciate all the response..
This is a source reference. Confirm exact model applicability in the original material.