5 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHCEL codes 0491 & 0492 = SAI ?
Reported or suspected cause
pump itself
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
If you hear/heard a sound like an angry high pitched vacuum or a saw cutting through thin sheet metal for a minute or so after a cold start it is likely the pump itself.
Leading evidence: 'pump itself' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'pump itself' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Clean carbon out of the disks' (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
If your pump has stopped working you might be able to take it apart and clean the carbon out of the disks that make up the air pump end of it.
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
Often it is carbon build up in the pump "vanes" that could be cleaned during a DIY pump disassembly/rebuild.
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
Or should I simply have a tech replace the pump regardless and tend to the other possible culprits at the same time just to be sure of addressing the problem?
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
Or should I simply have a tech replace the pump regardless and tend to the other possible culprits at the same time just to be sure of addressing the problem?
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
pump itself
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 you hear/heard a sound like an angry high pitched vacuum or a saw cutting through thin sheet metal for a minute or so after a cold start it is likely the pump itself.
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.
Pelican Parts: 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.
I had the dealer perform a scan due to CEL. The codes came back 0491 & 0492 = SAI. My question is what are the likely reasons for the SAI issue and ballpark cost to repair?
I'm of the understanding that the Secondary Air Injection system is designed to inject air into the exhaust intake which helps the car run rich on start-up to heat up the catalytic converter a little quicker?
This doesn't affect performance, or at least it hasn't yet, however, how long can it be driven this way before it gets worse if at all?
Opinions appreciated,
Thanks,
Mike
The secondary air injection is a system, not a device. As such, there are several components (air pump, air change over valve, vacuum switching valve, etc.) that can stick or fail, causing the pump to not activate, and you would get these codes. It could be something small or the pump itself maybe bad, but without further diagnostics, everything would be speculation.
Over time, a malfunctioning SAI can annoy the cats, which gets very expensive as the main cats are more than $2K US each. This is also an emissions issue, so the car may have inspection problems as well.
Drive it for a long time or until state inspection time.
The SAI system injects air into the exhaust upstream of the cats to get them to "light" sooner. It is a pollution control help.
If your pump has stopped working you might be able to take it apart and clean the carbon out of the disks that make up the air pump end of it. If the motor has failed you can buy a new Porsche branded Bosch SAI pump from Porsche for ~$1000 or get the same Bosch pump from a supplier for ~$300.
03 2003 Porsche 911 Air Pump - Air Intake - Bosch, Genuine - *********
I appreciate the input, thank you FPB111 for the info and link. I'm not that mechanically inclined or I would tackle this. Any idea what it will cost to identify the actual cause?
Or should I simply have a tech replace the pump regardless and tend to the other possible culprits at the same time just to be sure of addressing the problem?
Trying to get an idea of the worst case scenario re cost, the dealer service tech indicated its a matter of time to identify the actual cause and this could get somewhat expensive. I'd rather have some knowledge of what the possibilities are?
Any additional opinions?
Thanks,
Mike
Mike,
As JFP stated it could be any of the components in the SAI system.
Often it is carbon build up in the pump "vanes" that could be cleaned during a DIY pump disassembly/rebuild. (Probably not if you are not mechanical)
If you hear/heard a sound like an angry high pitched vacuum or a saw cutting through thin sheet metal for a minute or so after a cold start it is likely the pump itself.
The pump lives next to your left knee when you are standing looking into the engine bay. It is held in with 3 screws a connector and a hose. All are very easy to access. So a pump change is not a hard DIY.
On a cold start a dealer tech should be able to diagnose a bad SAI component in a few minutes with the PIWIS computer.
This is a source reference. Confirm exact model applicability in the original material.
