catalytic converters failed?
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
The pre is the small one located between the two o2 sensors on each bank the two mains have no sensors. The two small ones come to temp quicker and limit pollution faster. Unless the ops were defective something is wrong and needs to be diagnosed. Compression checks need to be done for oil blowby and also why an o2 sensor died when they last 100k.
Most often the cat death rattle comes from the main cats.Thats the big ones.
You can get magnaflow universals and splice them in if out of the 8year 80000mile warranty.Unless you are in California and magnaflow is working on getting carb approval for that one as well.
Most often the cat death rattle comes from the main cats.Thats the big ones.
You can get magnaflow universals and splice them in if out of the 8year 80000mile warranty.Unless you are in California and magnaflow is working on getting carb approval for that one as well.
MBWorld Fanatic!
Joined: Nov 2007
Posts: 2,078
Likes: 4
From: NYC
2012 C300 4Matic
Damn, and I had originally thought that was how it worked. Sorry about my previous posts saying otherwise. It's all Glyns fault. 
... I'm kidding Glyn we all make mistakes, but I had been lead to believe this from a few members posts including yourself.
... I'm kidding Glyn we all make mistakes, but I had been lead to believe this from a few members posts including yourself.
Super Member
Joined: Jul 2008
Posts: 929
Likes: 3
From: Portland, Oregon
2016 GLE 350
I can offer this: when my - what i am calling secondary cat - went bad, it rattled like a can of nails-much like any disinigrating cat converter does-and when the dealer replaced it, the tech i talked to called it the secondary cat, and refered to the first set of "cans" right after the exhaust manifolds as the primary cats.
With this in mind, that is why i claimed there are primary and secondary cats on the ( US at least) V6's.....
Anyhow, very curious as to a consensus on this. Happy Holidays to all. Greg
With this in mind, that is why i claimed there are primary and secondary cats on the ( US at least) V6's.....
Anyhow, very curious as to a consensus on this. Happy Holidays to all. Greg
Super Moderator
Joined: Jun 2008
Posts: 19,942
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
No probs Greg & acr. If I'm wrong, I'm wrong. I just wish to clarify. If I'm wrong a whole heap of South Africans are wrong. I sincerely apologise - I don't believe our cars are different here than yours.
MBWorld Fanatic!
Joined: Nov 2007
Posts: 2,078
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From: NYC
2012 C300 4Matic
This question is really becoming a bother!
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Joined: Feb 2009
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2006 C350 Sport 6MT
I still dont think they are real cats. I believe they are a different purpose.
I know people who take these off and still pass smog. why would they put "secondary cats" even if they are not needed for emissions.
I believe the cooling part 100%, Why? Because I remember when my friend removed his resonator off the G35 and he said he felt the the exhaust system got hotter. So i believe the heat part but for a cleaner air??? It's kind of hard to believe. also since there is nothing refering to them. The EPC or WIS don't even have any info on them. Even here:
http://www.trademotion.com/partlocat...layCatalogid=0
They have cats in the category and in pic they have nothing to purchase them.
I dont think these are real cats. If it was something important then they should have them everywhere. They even have the resonator in every EPC or WIS system even online but not these ("Secondary Cats")
I know people who take these off and still pass smog. why would they put "secondary cats" even if they are not needed for emissions.
I believe the cooling part 100%, Why? Because I remember when my friend removed his resonator off the G35 and he said he felt the the exhaust system got hotter. So i believe the heat part but for a cleaner air??? It's kind of hard to believe. also since there is nothing refering to them. The EPC or WIS don't even have any info on them. Even here:
http://www.trademotion.com/partlocat...layCatalogid=0
They have cats in the category and in pic they have nothing to purchase them.
I dont think these are real cats. If it was something important then they should have them everywhere. They even have the resonator in every EPC or WIS system even online but not these ("Secondary Cats")
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I still dont think they are real cats. I believe they are a different purpose.
I know people who take these off and still pass smog. why would they put "secondary cats" even if they are not needed for emissions.
I believe the cooling part 100%, Why? Because I remember when my friend removed his resonator off the G35 and he said he felt the the exhaust system got hotter. So i believe the heat part but for a cleaner air??? It's kind of hard to believe. also since there is nothing refering to them. The EPC or WIS don't even have any info on them. Even here:
http://www.trademotion.com/partlocat...layCatalogid=0
They have cats in the category and in pic they have nothing to purchase them.
I dont think these are real cats. If it was something important then they should have them everywhere. They even have the resonator in every EPC or WIS system even online but not these ("Secondary Cats")
I know people who take these off and still pass smog. why would they put "secondary cats" even if they are not needed for emissions.
I believe the cooling part 100%, Why? Because I remember when my friend removed his resonator off the G35 and he said he felt the the exhaust system got hotter. So i believe the heat part but for a cleaner air??? It's kind of hard to believe. also since there is nothing refering to them. The EPC or WIS don't even have any info on them. Even here:
http://www.trademotion.com/partlocat...layCatalogid=0
They have cats in the category and in pic they have nothing to purchase them.
I dont think these are real cats. If it was something important then they should have them everywhere. They even have the resonator in every EPC or WIS system even online but not these ("Secondary Cats")
Heaven knows! - If they are secondary Cats I don't understand why the post Cat O2 sensor is not mounted after them.
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