5 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHIAC malfunction ?
Leading reported evidence
Clean iac
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
Clean the IAC with carb cleaner, then use Q-tips and alcohol to clean the inside.
Leading evidence: 'Clean iac' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean iac' (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
Clean the IAC with carb cleaner, then use Q-tips and alcohol to clean the inside.
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
Start by cleaning the TB and IAC very good, Also clean the MAF with CRC MAF cleaner.
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
Start by cleaning the TB and IAC very good, Also clean the MAF with CRC MAF cleaner.
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
Just a thorough cleaning will often bring them back to life.
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.
5 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: 20261027T154520Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
My '99 911 has a crazy idle...at rest, tach needle swings from 1 to 2,000 rpm. The local tire shop pulled the codes and came up with p0506...IAC malfunction. After doing some research, the culprit sounds like a faulty Idle Air Controller. That's a new one on me, but I think the tire shop hit the nail on the head. Does this seem likely to rennlisters?
relinuca
I haven't dealt with the IAC on these cars, but on many other cars I have. Often times the IAC gets gummed up and its performance degrades. Just a thorough cleaning will often bring them back to life. Just a little elbow grease is free.
Definitely the IAC (or idle control valve). Remove throttle body and then take off the IAC. Be very careful of the thin paper gasket underneath. Clean the IAC with carb cleaner, then use Q-tips and alcohol to clean the inside. It will look black but it is supposed to be shiny sliver. You can operate (open and close) the valve with a 9V battery and some leads. It should move easily and smoothly.
If you have a really clean Throttle Body and a properly functioning engine/ air fuel ratio, (no vacuum leaks). you can disconnect the IAC wiring and the engine will idle at the base idle speed of about 500-600 rpm and stable.
The Idle speed goes up from base speed with the extra air of the IAC.
IF unplugging the IAC results in the engine stalling out, it is either not getting enough air around the Throttle Plate (dirty) or there is a vacuum leak causing very poor lean air/fuel ratio. (try adding some propane from a unlit propane torch to see if RPM increases dramatically)
Start by cleaning the TB and IAC very good, Also clean the MAF with CRC MAF cleaner.
My guess is you got a vacuum leak causing a lean condition and the engine is almost stalling then overreacts by energizing the IAC too much.
This is a source reference. Confirm exact model applicability in the original material.
