15 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHThe groove in the 996 header
Leading reported evidence
Use on the usa vehicles prior
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
i can only guess that the engines had this system since first built but perhaps were only used on the USA vehicles prior to Egas here .
Leading evidence: 'Use on the usa vehicles prior' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use on the usa vehicles prior' (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.
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.
15 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
911uk: 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: 20261026T105141Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi guys, I've searched but can't find the answer anywhere. What's the deal with the groove in the factory 996 header? Clearly it connects the exhaust ports with each other but why? I notice that neither the X51 header nor any of the aftermarket headers have this groove.
Its the pump on the left side of the engine .. right side and on the engine for turbos .
Parts for it listed here ..
https://www.deroure.com/diagrams.asp?TBL=2536&MAK=3&MDL=25&SMA=0&SMO=0&ST=&SC=0
Its fitted to all Uk Porsches as far as im aware due to emissions regulations .
Its there to fast warm the Cats so they start doing their job quicker .. lambda sensors have a heating element so same thing but done with voltage .
Save the planet stuff .
Not uncommon for the ports in the heads to coke up .. there are fault codes for this .
The groove is not actually on the header .. the gasket is shaped to allow the air flow .. from the picture then that should just be carbon buildup .
Ive no idear im afraid ..
MisterCorn comment makes perfect sense to me but the link shows a pre 99 pump so im confused .
i can only guess that the engines had this system since first built but perhaps were only used on the USA vehicles prior to Egas here .
All i can say is what the system does
I just bought gaskets for my '99, they came with a groove bent in them. I hope they are right....
£3.50 each, Elring is the OE manufacturer.
https://www.carparts4less.co.uk/cp4...cf117cf3b4de34aeca9a884f18f12a3bbfa604&000462
e-gas was introduced with the M96.02 in the C4 in MY1999. SAI was introduced with the M96.04 in MY2000 for cars with OBDII or Euro 3, according to Mr Streather.
MC
This is a source reference. Confirm exact model applicability in the original material.
