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Exhaust Lambda reading outside specified limits..

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

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YOUR RESEARCHExhaust Lambda reading outside specified limits..

Reported or suspected cause

exhaust leak

Reported cause

No successful repair reported for this finding.

1
Identified cause: 0
Suspected cause: 0
Reported fixes

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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 report identifying a cause: 1

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Reported cause · Original poster
I am under the impressison this is caused by an exhaust leak but the garage has fixed all the leaks and thinks its a vacuum leak, possibly the vacuum resovoir.
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Exhaust Lambda reading outside specified limits..

Frequently discussed work

Run fault it would seem

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion
the garage has jumped from an exhaust leak to a poor running fault it would seem ..
Original post Read captured discussion
Exhaust Lambda reading outside specified limits..

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Leading evidence: 'exhaust leak' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'exhaust leak' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Run fault it would seem' (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.

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1 matching discussions · 2 captured posts examined · 0 partial discussions

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Run fault it would seem

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion
the garage has jumped from an exhaust leak to a poor running fault it would seem ..
Original post Read captured discussion
Exhaust Lambda reading outside specified limits..

Frequently discussed actions (1)

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

Run fault it would seem

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
the garage has jumped from an exhaust leak to a poor running fault it would seem ..
Original post Read captured discussion
Exhaust Lambda reading outside specified limits..

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.

exhaust leak

No successful repair reported for this finding.

1
Identified cause: 0
Suspected cause: 0
Reported fixes

Read evidence and context

Discussions that report identifying 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.

Reported cause · Original poster
I am under the impressison this is caused by an exhaust leak but the garage has fixed all the leaks and thinks its a vacuum leak, possibly the vacuum resovoir.
Original post Read captured discussion
Exhaust Lambda reading outside specified limits..

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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.

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

911uk: 1 discussions

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Generation: 20261026T194705Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Ive had an MOT and Ive had the following failure: Exhaust Lambda reading after 2nd fast idle outside specified limits (8.2.1.2 (c)) Not that this is not failing on carbon monoxide or HC. The garage initially thought it was an exhaust leak which they have resolved but the car still doesnt pass. There are no fault codes present either. The car is standard 1999 C2 with the only modification is a Dansk back boxes. I am under the impressison this is caused by an exhaust leak but the garage has fixed all the leaks and thinks its a vacuum leak, possibly the vacuum resovoir. I thought any intake vacuum faults would be picked up in the ECU failt codes. Has anyone had any experiece of this issue? Thanks in advance, Antony.

POST 2Original post

when there are no fault codes then the garage needs to look at actual values .. this is what the car is doing .. you also have fuel trim .. depending on what that displays will lead you to the fault . A start .. look at lambda values pre and post cat .. is the post cat switching .. if so its a cat fault .. If pre then again are they switching .. too high or too low will indicate a rich or lean mixture .. this if a rich mixture will overtime kill a cat . the garage has jumped from an exhaust leak to a poor running fault it would seem .. that's a pretty big jump .. an exhaust leak will not cause a running issue whist a rich / lean mixture will ... it will show up on fuel trim and again lambda values . Do you have the actual fail values you can post from the print out ? btw .. if a cat fault then rev the car at 3k or higher for 5 mins .. get it stinking hot .. it then will probably pass .. overall though .. this is a fault you find from looking at the fuel trims and actual values of the lambdas etc .. can't say more than that . Edit .. Just to say a vacuum pipe disconnected and the car can easily compensate for it .. i very much doubt its that .

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