9 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHIrregular Idle
Leading reported evidence
Clean idle control valve
Suggestion or failed attempt
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 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 · Original poster
I'll clean the idle control valve and reset the DME and see if that works.
Leading evidence: 'Clean idle control valve' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean idle control valve' (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 · Original poster
Also, i should mention the MAV was cleaned about 6 months ago and at the time the outer (opposite of the plenum looked clean with no residue).
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 · Original poster
I'll clean the idle control valve and reset the DME and see if that works.
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.
9 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: 20261027T025149Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
I have a 1999 996 that has an irregular idle, but only when accelerating hard or going in reverse. When accelerating hard at high RPMs and then coming back down to idle, the RPMs might bounce once before settling down. If left to idle longer it might bounce up once or twice more over a period of a minute. Going in reverse at lower RMPs it does the same thing. The car does have a couple issues. First the accordion AOS connector was cracked several months ago. I fix that and it was driving fine until recently. It has a bad starter alternator wire and the ignition coils are cracked. I have an autocross event (150 mile round trip distance from me) that I want to attend so only have one weekend to work on the car before the event. My main worry is that the AOS might be going out, but the vacuum test is within spec and there is no smoke on start up. Are there other fault modes of the AOS that I might be missing? I would hate to hydrolock this car. Any ideas what might be causing this idle issue? Also, i should mention the MAV was cleaned about 6 months ago and at the time the outer (opposite of the plenum looked clean with no residue). I did unplug the battery several times this weekend while installing coilovers so maybe I did something to the ECU?
If the.manometer test was good then the aos is working. U have another issue...will the motor be ok to autocross, probably but until u find the issue???
You have a 99 so I'm guessing you have a cable throttle body. You need to clean your idle control valve. Do a search in this forum for idle control valve and how to clean.
The crossover valve in the intake are notorious for leaking . Find a chair tip or vacuum cap that fits and slide it on . For less than a couple bucks it might solve your problem .
^^ What he is talking about is the pivot point for the resonance flap on the rear crossover intake plenum. If memory works, it's a small rubber cap (9mm or is it 19mm?) that fits over the pivot point and seals it up. Known point for a vacuum leak. It would really show up with a smoke test. Also, make sure your oil filler pipe isn't cracked, usually where the straight section of pipe turns into the accordion section of pipe.
See some discussion here:
https://rennlist.com/forums/996-foru...ated-flap.html
And here:
https://rennlist.com/forums/996-foru...cuum-leak.html
And a discussion here:
https://www.pff.de/en/thread/2813670...take-manifold/
