6 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHunstable idle at cold start
Leading reported evidence
Adjust lambda sensor at the same time
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
Obviously they must have adjusted the Lambda sensor at the same time.
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
The engine computer uses this information to adjust the air/fuel mixture and other parameters to compensate for temperature, altitude, fuel grade, and other factors that affect how the engine is running.
Leading evidence: 'Adjust lambda sensor at the same time' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Adjust air/fuel mixture and other parameters' (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.
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
The engine computer uses this information to adjust the air/fuel mixture and other parameters to compensate for temperature, altitude, fuel grade, and other factors that affect how the engine is running.
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.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Adjust air/fuel mixture and other parameters
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
The engine computer uses this information to adjust the air/fuel mixture and other parameters to compensate for temperature, altitude, fuel grade, and other factors that affect how the engine is running.
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.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
1 acknowledgements have no verified action link; they do not establish a repair result.
Outcome without a verified action link
Ahh so that must be why the problem went away with the fabspeed install.
Recently my '03 996 C2 with 4K miles has started acting up a little on a cold start. Cold means the engine is cool but the ambient air temp is 70-85 degrees.
When starting the car, I need to let it idle for 20-30 seconds before driving. Giving it any gas causes it either to stall or hesitate. Is this a known problem? Dealer claims it is "common". This problem has worsened in the last couple of months (warmer temperatures?).
Hot starts are fine, and the car runs flawlessly otherwise.
I used to have this problem. It went away when I had my fabspeed exhaust fitted. The engineer said it had something to with the Lambda sensors whatever they are. Also, I take it you are using high octane fuel?
Actually, it would be good if someone could elaborate what Lambda sensors are.
My car idles at 1500rpm at cold start and then settles down to normal(1000) after about a minute. There has been much discussion about warming up the car before driving and many opinions vary as to how long to let it idle but most agree that you shouldn't drive your car right away after start. If you let it warm up for a minute or two it will probably be better.
The Lambda sensor, also called an O2 sensor or oxygen sensor, measures the amount of oxygen present in the exhaust gas. The engine computer uses this information to adjust the air/fuel mixture and other parameters to compensate for temperature, altitude, fuel grade, and other factors that affect how the engine is running.
Ahh so that must be why the problem went away with the fabspeed install. Obviously they must have adjusted the Lambda sensor at the same time.
Anyway, thanks for the info Mike.
I've had the same problem and have heard others complain too. Went away in winter. Has come back in summer. Forgot to mention it to dealer on recent service.
My guess is the computer is freaked out about ambient tmeperatures vs. oil/water temperature, in that the engine is not technically warm but its not cold either.
This is a source reference. Confirm exact model applicability in the original material.
