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CEL and reader indicated DMW

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THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

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YOUR RESEARCHCEL and reader indicated DMW

Leading reported evidence

Use o2 extenders

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Reported fixes: 0
Unsuccessful attempts: 1
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Suggestion
But he does say he had aftermarket cats installed, and I know a lot of people have had to use O2 extenders to fool the O2 sensors.
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CEL and reader indicated DMW

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Leading evidence: 'Use o2 extenders' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use o2 extenders' (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 · 8 captured posts examined · 0 partial discussions

Frequently discussed actions (1)

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Use o2 extenders

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
But he does say he had aftermarket cats installed, and I know a lot of people have had to use O2 extenders to fool the O2 sensors.
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CEL and reader indicated DMW

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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.

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

Rennlist: 1 discussions

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Generation: 20261027T000231Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Every so often I will get these two codes.....I clear them and they stay off for a while then pop back on. I did recently switch out to aftermarket cats and it seems it started after that. Any thoughts? Also is bank 1 driver side or passenger side? When I installed the O2 sensor I wonder if I messed up the wire(s) and twisted them to much?

POST 2Original post

Perhaps you could help us by identifying which two codes you are having.

POST 3Original post

Bank 1 is drivers side of the engine, and therefore the right exhaust pipe. Is the right exhaust tip oily or sooty? If you use something like Durametric software you can get a reading on each O2 sensor.

POST 4Original post

Quotes source post: 20052189

I believe his iCarsoft can do the same thing.

POST 5Original post

The code is P0420 - bank one converter efficiency. So either upstream or downstream O2 sensor, or both. But he does say he had aftermarket cats installed, and I know a lot of people have had to use O2 extenders to fool the O2 sensors. Maybe that is what his problem is.

POST 6Original post

aftermarket cats = sports cats = converter inefficiency = CEL P0420 ---> possible solution O2 sensor extender.

POST 7 / ORIGINAL POSTEROriginal post

Sorry for the stupid questions but why would it come up as "DME" then? I can try an extender and see what it does.

POST 8 / ORIGINAL POSTEROriginal post

Quotes source post: 20052189

No soot or oil on the exhaust tip.....

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