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Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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8 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHCar stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Leading reported evidence

Clean mass air flow sensor

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 · Original poster
Recently my car has been stalling when it idles (in neutral or when the clutch pedal is pressed), I got codes for MAF and Oxygen Sensors so I replaced the Oxygen Sensors and cleaned the MAF with a cleaner from the auto store.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Frequently discussed work

Clean maf is a waste

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
Cleaning the MAF is a waste.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Read full discussion summary

Leading evidence: 'Clean mass air flow sensor' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'air oil separator' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Clean maf is a waste' (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.

Read captured replies

1 matching discussions · 8 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Replace mass air flow sensor

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1
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've heard both sides of the argument, but I want to be sure it's not a vacuum leak or AOS problem before dishing out 200 dollars to replace a MAF that might still be working.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace oxygen sensors

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

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 · Original poster
Recently my car has been stalling when it idles (in neutral or when the clutch pedal is pressed), I got codes for MAF and Oxygen Sensors so I replaced the Oxygen Sensors and cleaned the MAF with a cleaner from the auto store.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run real bad

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

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
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

air oil separator

Suggestion or failed attempt

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
If it's tough to remove, like there's pressure in the system keeping it on (you'll hear a swoosh or sucking sound when removing it), then it's likely the AOS.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Frequently discussed actions (10)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Clean maf is a waste

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
Cleaning the MAF is a waste.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Clean mass air flow sensor

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

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 · Original poster
Recently my car has been stalling when it idles (in neutral or when the clutch pedal is pressed), I got codes for MAF and Oxygen Sensors so I replaced the Oxygen Sensors and cleaned the MAF with a cleaner from the auto store.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Combined work: Clean mass air flow sensor + Replace mass air flow sensor + Run real bad

No successful repair reported for this finding.

0
Reported fixes: 1
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that report an unsuccessful attempt: 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.

Unsuccessful attempt
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace mass air flow sensor

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1
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've heard both sides of the argument, but I want to be sure it's not a vacuum leak or AOS problem before dishing out 200 dollars to replace a MAF that might still be working.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace oxygen sensors

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

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 · Original poster
Recently my car has been stalling when it idles (in neutral or when the clutch pedal is pressed), I got codes for MAF and Oxygen Sensors so I replaced the Oxygen Sensors and cleaned the MAF with a cleaner from the auto store.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run ac

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 · Original poster
I noticed one time I was running the AC on idle, but then felt cold so I turned it off.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run car

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
I believe one way you can test the MAF is to try running the car with it unplugged.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run real bad

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

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
my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run remove the oil filler cap

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
With the car running remove the oil filler cap.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test maf is

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
I believe one way you can test the MAF is to try running the car with it unplugged.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Reported and suspected causes (1)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

air oil separator

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
If it's tough to remove, like there's pressure in the system keeping it on (you'll hear a swoosh or sucking sound when removing it), then it's likely the AOS.
Original post Read captured discussion
Car stalling when idling, AOS or Vacuumn Leak? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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.

8 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

986Forum: 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
You didn't mention whether you're still getting codes after the oxygen sensor replacement.
Original post Read captured discussion
No unique explicit quoted action; no causal link assigned

Generation: 20261026T212127Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Recently my car has been stalling when it idles (in neutral or when the clutch pedal is pressed), I got codes for MAF and Oxygen Sensors so I replaced the Oxygen Sensors and cleaned the MAF with a cleaner from the auto store. The car runs much more smoothly now, definite increase in power and the idle is much smoother WHEN IT IDLES. The problem is, half the time when I let it idle at a stoplight it will stall, but it starts again immediately. I noticed one time I was running the AC on idle, but then felt cold so I turned it off. Upon turning the AC off it did stall instantly, but again started immediately. Could this be a vacuum leak? AOS fault? Maybe the MAF needs to be replaced? If it is a Vacuum leak or AOS, are these easy DIY fixes or should I send it off to a mechanic? I'm still quite a novice when it comes to mechanics but I do know my way around.

POST 2Original post

my 98 was running real bad check engine light was on also real sluggish and boggy ,and I tried cleaning the maf with mas air cleaner, it did not work ,just a waste of time ,so I replaced it cost about $200 shipped to my door 20 min to install, fixed the problem it runs a lot better ,I do not think cleaning them works ,

POST 3 / ORIGINAL POSTEROriginal post

I've heard both sides of the argument, but I want to be sure it's not a vacuum leak or AOS problem before dishing out 200 dollars to replace a MAF that might still be working.

POST 4Original post

Saw another post recently about testing to determine whether the AOS is bad or going bad. With the car running remove the oil filler cap. If it's tough to remove, like there's pressure in the system keeping it on (you'll hear a swoosh or sucking sound when removing it), then it's likely the AOS. If you haven't see any of the infamous AOS tail pipe white smoke clouds, that's probably not the problem. Don't think the AOS causes your symptoms. A bad MAF sounds more likely. I believe one way you can test the MAF is to try running the car with it unplugged. If it runs better, the MAF is likely shot. Someone else more knowledgeable about this will likely chime in. Lots of MAF posts on this forum. Have you read them all? If you need to buy an MAF stay away from eBay. I've heard ********************************az has got just about the best price and, unlike eBay, you'll get the correct part. You didn't mention whether you're still getting codes after the oxygen sensor replacement. How many miles on your car?

POST 5Original post

If you got a maf code ,and you did not replace it ,thats prollay what it is ,cleaning them normally does not work ,my 1998 has had two mafs and it has 88 k on it

POST 6Original post

Cleaning the MAF is a waste. www.************************************************************ best place around.

POST 7Original post

this is what my neighbors car did just this weekend - heavy smoke, and the cap took two hands to remove. I think I heard a whirrrrrrrrr sound coming from the AOS...but I'm not positive. Keep us updates!

POST 8Original post

You can use an (unlit) propane torch to help diagnose vacuum leaks, as the engine will increase RPM when you wave it near a leaking hose. -james

This is a source reference. Confirm exact model applicability in the original material.