8 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHIrratic Idle After Hard Driving!
Leading reported evidence
Install with e-gas do not have an idle control valve
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
Later models fitted with e-Gas do not have an idle control valve.
Leading evidence: 'Install with e-gas do not have an idle control valve' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'material fatigue in the rubber/cloth reinforced diaphram' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check throttle body' (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.
material fatigue in the rubber/cloth reinforced diaphram
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
I found a crack from I suspect material fatigue in the rubber/cloth reinforced diaphram.
passenger side variocam solenoid and variocam actuator
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
Another time, much more recent, the idle started doing swinging again, and this time severe enough on the low side I thought the engine was going to stall, and the cause turned out to be a bad passenger side VarioCam solenoid and VarioCam actuator.
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
Anyhow, another check you can perform on your way to confirming or eliminating the AOS is to check the throttle body for presence of oil.
passenger side variocam solenoid and variocam actuator
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
Another time, much more recent, the idle started doing swinging again, and this time severe enough on the low side I thought the engine was going to stall, and the cause turned out to be a bad passenger side VarioCam solenoid and VarioCam actuator.
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.
8 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: 20261026T152433Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi guys,
I realised that after some hard street driving, when i reach home and park my porky, the idling would get all irratic. It would drop to about 500rpm for a second and then move back up to 800rpm and idle in the range from 600rpm to 800rpm and at times drop to 500rpm .... Ideas?
Cheers
My 02 Boxster suffered a similar symptom as the original AOS was going bad. A hunting idle was one of the first symptoms, though this was a long time ago and my memory is fuzzy but I don't recall the idle swings that severe.
And no check engine light.
Another time, much more recent, the idle started doing swinging again, and this time severe enough on the low side I thought the engine was going to stall, and the cause turned out to be a bad passenger side VarioCam solenoid and VarioCam actuator. But in this case the CEL came on and an error code was logged that pointed to the VarioCam system. Maybe P1539 (Camshaft adjustment bank #2).
Sincerely,
Macster.
What is the make/model and year of your car and what's the mileage? IIRC early 996 models (equipped with the 3.4l engine?) came with an idle control valve. Later models fitted with e-Gas do not have an idle control valve.
A dirty/malfunctioning idle control valve can result in an erratic idle.
For a suspected AOS there are a couple of things you can do to possibly confirm that the symptom is from a failing AOS.
One is to with the engine idling unscrew and remove the oil filler tube cap. Sometimes a failing AOS causes such a huge pressure difference in the engine crankcase compared to outside of the engine crankcase the cap is nearly impossible to impossible to remove.
However, if you can remove it with ease this is not 100% proof the problem is not the AOS. Either AOSs can fail in one of several ways and some of the symptoms vary or the AOS manifests different symptoms as it goes from slightly feverish to just before it reaches death's door. I sort of favor the latter since I cut open one bad AOS and there ain't that much to go wrong inside of one. I found a crack from I suspect material fatigue in the rubber/cloth reinforced diaphram. My belief is as this crack or initially a pinhole grows in size the symptoms transistion.
Anyhow, another check you can perform on your way to confirming or eliminating the AOS is to check the throttle body for presence of oil. To do this you'll have to remove the TB.
The AOS connects to the manifold at a connector behind (downstream) of the TB (at least on my Boxster but I think the layout's similar for the 996 engine) and a failing AOS can pass a lot of oily vapor into the intake.
Due to the proximity of the TB to this connector the TB can become rather oily.
If you find this condition, again this points to the AOS but does not rule out another cause for the engine's behavior.
Sincerely,
Macster.
