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Cats and CEL

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18 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHCats and CEL

Leading reported evidence

Run hard

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
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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 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

Funny, ran hard on the track, no CEL.

Cats and CEL
Read full discussion summary

Leading evidence: 'Run hard' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'specific cel' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Run hard' (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.

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1 matching discussions · 18 captured posts examined · 0 partial discussions

Compare 2 other evidence results

specific cel

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 · Original poster

The issue is the specific CEL that would come up is that the O2 sensor woudl have failed, not that the CAT was faulty.

Cats and CEL

Run risk of ticking off the dealer and/or needing

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 · Original poster

If generic then this approach would work, if it can distinguish between for example a clogged cat or simply a faulty sensor then i run the risk of ticking off the dealer and/or needing to go to a different solution than a new replacement from the dealer.

Cats and CEL
Frequently discussed actions (2)

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

Run hard

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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

Funny, ran hard on the track, no CEL.

Cats and CEL

Run risk of ticking off the dealer and/or needing

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 · Original poster

If generic then this approach would work, if it can distinguish between for example a clogged cat or simply a faulty sensor then i run the risk of ticking off the dealer and/or needing to go to a different solution than a new replacement from the dealer.

Cats and CEL
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.

specific cel

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 · Original poster

The issue is the specific CEL that would come up is that the O2 sensor woudl have failed, not that the CAT was faulty.

Cats and CEL
Coverage and how to read this overview

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.

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

  • Rennlist: 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

POST 1 / ORIGINAL POSTEROriginal post

Ok so here is the deal that I need hep/advice on: About 2 weeks ago start getting a rattling noise from the engine bay. Freaking out thinking that I am in for "That Post" that nobody likes to make. Dealer pulls it in and says that it is only the cats rattling. PHEW! Then he says it is $1500 to replace them. Ouch. He does not recomend that though because they are required to replace if the car is less then 7 years old and/orunder 70k miles. I qualify so thats cool. Catch is the CEL light needs to go on before he can do that. Been a couple weeks and no light. Sounds like a Diesel engine and hate that it appears that i am driving a car on its last legs. The question: How can i get that light to come on like right now?

POST 2Original post

pull off one of the o2 sensor from the cat... turn the car on, that should trigger a cel. Put it back on and hopefully will stay on, on the way to the dealer.

POST 3 / ORIGINAL POSTEROriginal post

You rock - will try that immediately.

POST 4Original post

Bill, I had this happen on both of my cats. I didn't have to wait very long - the light came on within a couple of days.

POST 5Original post

Quotes source post: 5867803

Disconnecting the O2 sensor will easily be seen as a sensor failure and NOT a CAT failure. Different code generated for CAT failure than you will get with a bad O2 sensor. Could erase any trust the dealer has in you.

POST 6 / ORIGINAL POSTEROriginal post

yeah was talking about that with some other car guys over lunch and realizing that very fact. Different code entirely and while the service manager and I are quite friendly, do not want to come in with the wrong code. He advised i just drive it really hard and the light should come on eventually while the cat continues to bust apart. Is that my only option?

POST 8Original post

How is unscrewing a sensor off the cat gonna cause a sensor failure.... its still connected. it'll show a bad read and throw a cel... if you want it now, this is the only way.... The question is which sensor, before, after the cat, or both. Driving hard will do it as well or you may have to drive for awhile...

POST 9 / ORIGINAL POSTEROriginal post

The issue is the specific CEL that would come up is that the O2 sensor woudl have failed, not that the CAT was faulty. The advisor specifically said that when it breaks up inside it blocks exit, so perhaps the after-cat sensor would detect that. If this is the sensor that would detect the variation, then is it tied to a single particular error or is it generic? If generic then this approach would work, if it can distinguish between for example a clogged cat or simply a faulty sensor then i run the risk of ticking off the dealer and/or needing to go to a different solution than a new replacement from the dealer.

POST 10Original post

Quotes source post: 5867778

slow -- like through town with 35mph or lower limits and lots of stop signs, and red lights but shutting engine off before fully warmed it up -- which is rare for me -- and then a hour or two later taking car out for a longer drive. Usually during this second outing light will come on. Another scenario is after driving 30 miles and the last 20 or so miles freeway driving and then leaving freeway and driving through town to my house CEL will come on. Colder temperature seems to play a role, but really in my car's case the converter is just worn out. That can happen after 203000+ miles. CEL can't come on if you don't drive car. So drive it. If converter really shot, either worn out, or suffering from mechanical failure, a CEL will be the result. Sincerely, Macster.

POST 11Original post

I just had my bank 1 cat replaced for this week for this very reason. Funny, ran hard on the track, no CEL. Drove a 2 hr rally the same day and the CEL came on. My bet is it will come on soon. Mine rattled for about 2 weeks before it came on.

POST 12Original post

The codes for cat failure are usually "bank x catalyst operating below threshold", which is measured by O2 no? I bet backing out the 2nd O2 inline (but still wired and live) would throw a below threshold CEL as suggested by redridge. I just don't want my fingerprints on the O2 when they diagnose, risk/reward not there for me. If I was running out of warranty, I might be a little more cavalier.

POST 13Original post

Quotes source post: 5869390

essentially you are simulating a bad cat condition by doing this... Im glad someone sees my reasoning... the condition was... the OP wanted the cel to light up NOW.

POST 14 / ORIGINAL POSTEROriginal post

I think I am gonna wait nother week of driving at least. I definitely do not want to try and trick my dealer per se - just wanted to know if there was a particluar driving behavior that would trigger the CEL.

POST 15Original post

My dealer covered my Cats at 90K, said warranty was to 100K which, is a Federal law

POST 16 / ORIGINAL POSTEROriginal post

Interesting - mine said 70k or 7 years....

POST 17Original post

varies by year, just read your owners manual it's in there for your specific vehicle

POST 18Original post

put a gallon of leaded race gas in a nearly empty tank........... THAT will cause your cats to fail.

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