Removing CATS
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Joined: Mar 2010
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
Removing CATS
A couple of us on this forum are considering it however it will most likely turn on check engine light plus voids the warranty (witch i dont care about I never take it to the dealer) I can always put it back.
Question to all of you benz owners, besides the obvious as I mentioned about the check engine light and the warranty anything else we should know before doing it?
-Will it damage anything else on the car?
-Has anyone done it before dose it sound like ****?
DO NOT reply if you dont know and just want to make a smart comment example:
"Why would you do that in the first place?"
"It will sound horrible!"---thats what some people said about removing mufflers and resonators and it turned out great.
Question to all of you benz owners, besides the obvious as I mentioned about the check engine light and the warranty anything else we should know before doing it?
-Will it damage anything else on the car?
-Has anyone done it before dose it sound like ****?
DO NOT reply if you dont know and just want to make a smart comment example:
"Why would you do that in the first place?"
"It will sound horrible!"---thats what some people said about removing mufflers and resonators and it turned out great.
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Joined: Oct 2009
Posts: 85
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From: Detroit Area
2008 C350 Sport
You forgot to bring up the most important point, and the reasons that the CATS are on the car in the first place:
Environmental Impact
Why would you want to remove them? Just for the "sound"? Really?
Environmental Impact
Why would you want to remove them? Just for the "sound"? Really?
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Joined: Sep 2009
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From: Dix Hills, New York
2012 C250 Coupe
It would definitely turn on the check engine light. I know a guy who removed the cats on his v8 mustang gt. It is loud as hell because of that. Personally, I think it sounds good, but it is a v8, I can only speculate that a v6 will sound louder, but the louder sound may not sound good and throaty like the v8. Obviously, he needs to replace the cats for emission inspections yearly, which is annoying.
Aside from the cosmetic side, because there will be no downstream oxygen sensor, the car won't know how the exhaust coming out of the car is, and will only adjust based on optimal fuel/air mixture in the main in-engine oxygen sensor. This means that your engine will create more power, but also use more fuel. Not to mention the environmental impact. Unregulated engines (such as watercrafts like jetskis riding for 2 hours ie no cats) emit as much pollutants as driving a modern regulated engine (ie cats installed) car 130,000 miles.
Aside from the cosmetic side, because there will be no downstream oxygen sensor, the car won't know how the exhaust coming out of the car is, and will only adjust based on optimal fuel/air mixture in the main in-engine oxygen sensor. This means that your engine will create more power, but also use more fuel. Not to mention the environmental impact. Unregulated engines (such as watercrafts like jetskis riding for 2 hours ie no cats) emit as much pollutants as driving a modern regulated engine (ie cats installed) car 130,000 miles.
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
correct just for the sound! Environmental Impact is something I could care less about and people dont get pissed of becuase I dont just answer the question I asked.
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
It would definitely turn on the check engine light. I know a guy who removed the cats on his v8 mustang gt. It is loud as hell because of that. Personally, I think it sounds good, but it is a v8, I can only speculate that a v6 will sound louder, but the louder sound may not sound good and throaty like the v8. Obviously, he needs to replace the cats for emission inspections yearly, which is annoying.
Aside from the cosmetic side, because there will be no downstream oxygen sensor, the car won't know how the exhaust coming out of the car is, and will only adjust based on optimal fuel/air mixture in the main in-engine oxygen sensor. This means that your engine will create more power, but also use more fuel. Not to mention the environmental impact. Unregulated engines (such as watercrafts like jetskis riding for 2 hours ie no cats) emit as much pollutants as driving a modern regulated engine (ie cats installed) car 130,000 miles.
Aside from the cosmetic side, because there will be no downstream oxygen sensor, the car won't know how the exhaust coming out of the car is, and will only adjust based on optimal fuel/air mixture in the main in-engine oxygen sensor. This means that your engine will create more power, but also use more fuel. Not to mention the environmental impact. Unregulated engines (such as watercrafts like jetskis riding for 2 hours ie no cats) emit as much pollutants as driving a modern regulated engine (ie cats installed) car 130,000 miles.
Member
Joined: Jul 2009
Posts: 209
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From: Germantown MD
08 c350
I dont' know if this can be used for our cars, but in my old car people used o2 sim to cancel out the check engine light. I had a standalone engine management so I could just plug my laptop and disable the check engine light, but for the people that didn't get any sort of ecu management, o2 sim was the way to go.
as for the sound, my car was a 4 cyl, and it made it sound RASPY. but it's a 4cyl and they just tend to sound more raspy. I actually think that it would sound good on a v6 since I've seen some 350z's and it sounded good.
as for the sound, my car was a 4 cyl, and it made it sound RASPY. but it's a 4cyl and they just tend to sound more raspy. I actually think that it would sound good on a v6 since I've seen some 350z's and it sounded good.
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MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
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Joined: Aug 2009
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From: Charlotte, NC
2015 BMW M235i 6MT
Your setup with your x-pipe and straight pipes (which you never posted pictures of) already sounds awesome! I can't imagine what it would sound like with no cats. You should definitely do it!
Super Member
Joined: Nov 2009
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From: Westchester, NY
2009 C-300 Sport
So I have already removed the resonator and put an X-Pipe, now i was thinking on removing just the secondary cats and put straight pipes, is there a sensor in the secondary cats and will it make the check engine light pop up in the dashboard? The reason why Im asking this is cause my friend has a C63 and he removed the resonator and secondary cats and replaced it with straight pipes and nothing has happen besides the car being louder and I guess the air flowing better but i don't know if the C300 has some kind of sensor that the C63 doesn't have?
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From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
A couple of us on this forum are considering it however it will most likely turn on check engine light plus voids the warranty (witch i dont care about I never take it to the dealer) I can always put it back.
Question to all of you benz owners, besides the obvious as I mentioned about the check engine light and the warranty anything else we should know before doing it?
-Will it damage anything else on the car?
-Has anyone done it before dose it sound like ****?
DO NOT reply if you dont know and just want to make a smart comment example:
"Why would you do that in the first place?"
"It will sound horrible!"---thats what some people said about removing mufflers and resonators and it turned out great.
Question to all of you benz owners, besides the obvious as I mentioned about the check engine light and the warranty anything else we should know before doing it?
-Will it damage anything else on the car?
-Has anyone done it before dose it sound like ****?
DO NOT reply if you dont know and just want to make a smart comment example:
"Why would you do that in the first place?"
"It will sound horrible!"---thats what some people said about removing mufflers and resonators and it turned out great.
Personally, carving up the all stainless steel exhaust system seems unthinkable to me.
Last edited by RLE; Nov 16, 2010 at 07:03 PM.
MBWorld Fanatic!
Joined: Sep 2007
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From: Southeast
2008 C300 Sport, RWD, US
As a California resident, I'm surprised that you don't know that you won't be able to license the car the next time because of the stored failure code. Further, the mixture is regulated by inputs from the four O2 sensors. Here in Washington the first emission test is after the car is five year sold but CARB being what it is, that may not be California's practice.
Personally, carving up the all stainless steel exhaust system seems unthinkable to me.
Personally, carving up the all stainless steel exhaust system seems unthinkable to me.
I tend to think that if he was a California resident, he'd already be aware of the polution testing impact and if he lived in Louisiana, he wouldn't care.
I on the other hand like to hear just how quiet my car runs on new asphalt. I really don't want anything to make the car louder. Had I wanted that, I'd get a muscle car.
Member
Joined: Nov 2009
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2008 C350
for yearly inspection,, there are always places where they do it on the low.. meaning they don't test anything, they put this hacked device between the machine and your ports.. if there are shops like that in ny, im pretty sure there are shops like that in cali or anywhere.. i know about the pollution issue but i've always heard straight pipes with no cat being the best..
Senior Member
Joined: Mar 2009
Posts: 451
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From: S.F. Bay Area
2008 C300 Sport, 2010 RX350 AWD
1. remove your CATS will cause you to fail both smog and visual inspection
2. if you are caught w/ CATS removed, you will face a fine between $2,500 - $3,000 here in CA
3. CHP are trained to spot illegally modifed cars and sounds of cars w/ CATS removed are pretty easy to identify
4. any smog shop that was caught for giving false report or false smog certificate faces maximun fine of $250,000
5. w/o CATS, your CEL will come on and your EGR won't work, fuel consumption will suck for sure..
If all you want is better sound from your exhaust, there are other and safer way to get it done..
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
take a look at the state approved aftermarket CATS list above
2. if you are caught w/ CATS removed, you will face a fine between $2,500 - $3,000 here in CA
3. CHP are trained to spot illegally modifed cars and sounds of cars w/ CATS removed are pretty easy to identify
4. any smog shop that was caught for giving false report or false smog certificate faces maximun fine of $250,000
5. w/o CATS, your CEL will come on and your EGR won't work, fuel consumption will suck for sure..
If all you want is better sound from your exhaust, there are other and safer way to get it done..
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
take a look at the state approved aftermarket CATS list above
Thread Starter
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Joined: Mar 2010
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
for yearly inspection,, there are always places where they do it on the low.. meaning they don't test anything, they put this hacked device between the machine and your ports.. if there are shops like that in ny, im pretty sure there are shops like that in cali or anywhere.. i know about the pollution issue but i've always heard straight pipes with no cat being the best..
Thread Starter
Member
Joined: Mar 2010
Posts: 214
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
1. remove your CATS will cause you to fail both smog and visual inspection
2. if you are caught w/ CATS removed, you will face a fine between $2,500 - $3,000 here in CA
3. CHP are trained to spot illegally modifed cars and sounds of cars w/ CATS removed are pretty easy to identify
4. any smog shop that was caught for giving false report or false smog certificate faces maximun fine of $250,000
5. w/o CATS, your CEL will come on and your EGR won't work, fuel consumption will suck for sure..
If all you want is better sound from your exhaust, there are other and safer way to get it done..
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
take a look at the state approved aftermarket CATS list above
2. if you are caught w/ CATS removed, you will face a fine between $2,500 - $3,000 here in CA
3. CHP are trained to spot illegally modifed cars and sounds of cars w/ CATS removed are pretty easy to identify
4. any smog shop that was caught for giving false report or false smog certificate faces maximun fine of $250,000
5. w/o CATS, your CEL will come on and your EGR won't work, fuel consumption will suck for sure..
If all you want is better sound from your exhaust, there are other and safer way to get it done..
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
take a look at the state approved aftermarket CATS list above
even with my audi a4 2008 I got pulled over over 7 times in 2 months for different reasons and I had a cat back straight pipe witch is very similar sound you would have with not cats, not one mentioned anything about the exhaust they are not that good that they would know the difference. I dont think it would make it that much louder than it already is and I did get pulled over a couple of times on my benz and nothing was mentioned to me, when they spot Hondas or other riced out cars they know right away there are mods involved but on cars like ours not a lot of people do it so they assume its like that or wont say anything. But I agree if you fall on a ***** cop and he breaks out the decibel meter....you get towed (but i would ask for his supervisor first) lol BUT thats a 5% to 10% chance I think I might be willing risk.
I have to look to see how much its going to cost but thats a good Idea.
"If all you want is better sound from your exhaust, there are other and safer way to get it done."
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
Member
Joined: Oct 2010
Posts: 129
Likes: 0
White 2010 C300 Sport
1. remove your CATS will cause you to fail both smog and visual inspection
2. if you are caught w/ CATS removed, you will face a fine between $2,500 - $3,000 here in CA
3. CHP are trained to spot illegally modifed cars and sounds of cars w/ CATS removed are pretty easy to identify
4. any smog shop that was caught for giving false report or false smog certificate faces maximun fine of $250,000
5. w/o CATS, your CEL will come on and your EGR won't work, fuel consumption will suck for sure..
If all you want is better sound from your exhaust, there are other and safer way to get it done..
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
take a look at the state approved aftermarket CATS list above
2. if you are caught w/ CATS removed, you will face a fine between $2,500 - $3,000 here in CA
3. CHP are trained to spot illegally modifed cars and sounds of cars w/ CATS removed are pretty easy to identify
4. any smog shop that was caught for giving false report or false smog certificate faces maximun fine of $250,000
5. w/o CATS, your CEL will come on and your EGR won't work, fuel consumption will suck for sure..
If all you want is better sound from your exhaust, there are other and safer way to get it done..
http://www.arb.ca.gov/msprog/aftermk...ftermktcat.htm
take a look at the state approved aftermarket CATS list above
damm you make me laugh...get outta here...removing your cats DOESNT give any engine lights
MBWorld Fanatic!
Joined: Sep 2009
Posts: 2,108
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From: Dix Hills, New York
2012 C250 Coupe
In my girlfriend's accord she has a second oxygen sensor right after (technically it is part of) the cat. It is heated and it tells the car the exhaust air oxygen mix, and the motor will adjust accordingly. If this is removed, it will throw a CEL. I don't know if our benz has this secondary heated oxygen sensor (or any oxygen sensor for that matter. But I would assume it does..
Member
Joined: Oct 2010
Posts: 129
Likes: 0
White 2010 C300 Sport
In my girlfriend's accord she has a second oxygen sensor right after (technically it is part of) the cat. It is heated and it tells the car the exhaust air oxygen mix, and the motor will adjust accordingly. If this is removed, it will throw a CEL. I don't know if our benz has this secondary heated oxygen sensor (or any oxygen sensor for that matter. But I would assume it does..
Theres no comparison to a honda and a Benz..
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
