6 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHFailed MoT - CO Emissions
Leading reported evidence
Check with no improvement
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
I'd previously cleaned the MAF and had the emissions re-checked with no improvement.
Leading evidence: 'Check with no improvement' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check with no improvement' (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 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
I'd previously cleaned the MAF and had the emissions re-checked with no improvement.
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
A long-ish saga, but after failing an MoT a couple of weeks ago on CO emissions and various hints and tips from 911UK, used the Durametric to read the error codes and sure enough I had the 'Cat Efficiency below threshold' on both banks.
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.
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.
Combined work: Clean maf and had the emissions re + Use durametric
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 · Original poster
A long-ish saga, but after failing an MoT a couple of weeks ago on CO emissions and various hints and tips from 911UK, used the Durametric to read the error codes and sure enough I had the 'Cat Efficiency below threshold' on both banks. I'd previously cleaned the MAF and had the emissions re-checked with no improvement.
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
A long-ish saga, but after failing an MoT a couple of weeks ago on CO emissions and various hints and tips from 911UK, used the Durametric to read the error codes and sure enough I had the 'Cat Efficiency below threshold' on both banks.
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.
6 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Porsche Club GB: 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: 20261026T205155Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
A long-ish saga, but after failing an MoT a couple of weeks ago on CO emissions and various hints and tips from 911UK, used the Durametric to read the error codes and sure enough I had the 'Cat Efficiency below threshold' on both banks. I'd previously cleaned the MAF and had the emissions re-checked with no improvement. I ended up at
Zero Exhausts
near Ashford in Kent. A real, proper old school engineering concern run by Kevin, who clearly knows exactly what he's doing and is obviously a real perfectionist. Have a look at his website to see some of the stuff he's done. I can't recommend him highly enough. I suspect he'd do a fantastic and inexpensive job of the 'bypass mod' for N/A 996's and 997's. He sourced the right 200 cell, high BHP cats and re-fabricated my existing exhaust - loads cheaper than buying a new one! It fits perfectly and is a work of art. He even rotated the position of the Lambda sensors so they're now easier to access and there's room for the post-cats to have more standoff in case of CEL problems. It actually sounds better than the original and so far so good after 80 miles, no error codes. Here's a picture of the completed exhaust. Now to test the emissions again!
Many thanks for the update and pic's.
I love good old fashioned common sense solutions using proper engineering. Hate the current trend of 'part swapping'.
Mine's one of the Kline Innovation prototypes (hence, I suspect, the Cat failure). Kline now use a decent 'bolt in' cat, I think. But if you've ever heard a Kline exhaust on a Turbo, I think you'd be impressed. It definitely 'growls'! If you're nearby, I'd be happy to take you out for a spin to see for yourself.
