Just removed 2nd cat and ....

Sam12345 · 02-20-2009, 12:22 AM

Ok, so i have
Catless downpipes, JB3, and Aftermarket mufflers.

The car sounded fine, and the only time the car ever smelled was during the cold start

Today i went to a well known exhuast shop and had my 2nd cats removed

Afterwords....

The car starts making a VERY LOUD rattling noise, around 2k RPM. Everytime i shift and it goes to 2k it makes the noise. I have to stay in high RPMs to avoid it.

I suppose this is bad welding?

Problem 2....the car smells so FUCKING BAD. when i am stopped and my car is idoling with windows open i completly smell it. I know it was going to smell worse, but come on i didnt think it would smell this bad.

Could the extra smell be from a leak from the poor welding?

Thanks guys

enrita · 02-20-2009, 12:25 AM

think they did not a good job by removing the CAT . Go back to them and check . Could be leaking or something.

Bimmer Nerd · 02-20-2009, 12:30 AM

yea it might be poor welding and most likely its some kind of a leak.

Sam12345 · 02-20-2009, 12:39 AM

definatly going back tommorow, honestly i feel dizzy a bit from the fumes still. it was ridiculously smelly.

pdjafari · 02-20-2009, 12:39 AM

i always thought a ticking sound was a sign of an exhaust leak??

addicted2drums · 02-20-2009, 12:52 AM

I have seen several posts from people that have removed the second cats complaining about the smell, so i think that is normal for that mod.

hotrod182 · 02-20-2009, 04:26 AM

Quote:

Originally Posted by addicted2drums

I have seen several posts from people that have removed the second cats complaining about the smell, so i think that is normal for that mod.

Yeah, I have witnessed this too. Gives me a headache, and people around you will definitely know you have your cats removed. Something I won't do. They sometimes have check points where they will check for cats, etc. If you get caught without the cats, its pretty stiff penalties...Federal Violation I believe. DPs are a different story, I don't think most of law enforcement knows what to look for on the down pipes.

enrita · 02-20-2009, 04:36 AM

Fully catless is in my opinion pretty bad. at least one set should be in. and for what ? 5 hp gain???

rcracer_tx · 02-20-2009, 04:43 AM

Quote:

Originally Posted by enrita

Fully catless is in my opinion pretty bad. at least one set should be in. and for what ? 5 hp gain???

I agree, completely catless is not that much better than a set of simple downpipes while keeping the secondary cats, or replacing those with high flow ones.

Andras · 02-20-2009, 07:10 AM

Quote:

Originally Posted by rcracer_tx

I agree, completely catless is not that much better than a set of simple downpipes while keeping the secondary cats, or replacing those with high flow ones.

that's why I ordered (and installed) my AE exhaust with high flow (secondary) cats put on purpose

Sam12345 · 02-20-2009, 09:14 PM

ye guys, the noise was from a small leak.

but regardless the car smelled SOO FUCKING BAD!

i kid you not, i had my friend do a drive by for me, and i suffocated for a solid 30 seconds after he passed. You cannot roll your windows down unless cruising at 10mph+.

fuck 2nd cat delete

E92White · 02-20-2009, 09:18 PM

did you feel any difference in performance ?

Sam12345 · 02-20-2009, 09:22 PM

Quote:

Originally Posted by E92White

did you feel any difference in performance ?

not really in perfomance.

the car was a noticeably louder without 2nd cats, sounded inredibly and redline.

however id rather have a bit less hp, and a bit less noise then die of suffocating.

cn555ic · 02-20-2009, 10:21 PM

Damn I wonder why guys that are completely catless don't ever say that the car has such a bad smell....I am thinking about it, but probably wait for the CPE catted ones!!! I would not want to be getting any headaches from the smell

CaptChaos · 02-21-2009, 12:34 AM

What does it smell like?

SfValley335i · 02-21-2009, 01:04 AM

Quote:

Originally Posted by cn555ic

Damn I wonder why guys that are completely catless don't ever say that the car has such a bad smell....I am thinking about it, but probably wait for the CPE catted ones!!! I would not want to be getting any headaches from the smell

I would smell the fumes while in the Drive thru of some fast food joints... I would also smell it after parking the car and walking out.

I think the smell is bearable but nothing you would want to smell... I think it took me about a week to get over the smell or maybe it stopped smelling...

Performance gains from removing 2nd cats is very minimal. I think I only noticed the gains in the mid range rpm...

gian335 · 02-21-2009, 01:11 AM

it smells pretty bad when its cold, when the car warms up its a little better. but u can still smell it when ur around the car when its on (idling).

gian335 · 02-21-2009, 01:13 AM

do the secondary cats tame down the smell a little bit, if u have catless downpipes?

midlife · 02-21-2009, 09:30 AM

Quote:

Originally Posted by hotrod182

Yeah, I have witnessed this too. Gives me a headache, and people around you will definitely know you have your cats removed. Something I won't do. They sometimes have check points where they will check for cats, etc. If you get caught without the cats, its pretty stiff penalties...Federal Violation I believe. DPs are a different story, I don't think most of law enforcement knows what to look for on the down pipes.

terry (BMS juicebox) warned us that if you have catless dps, removing the "quite efficient" stock 2nd cats and mufflers would yield little to no whp gain.
he tired this himself and said that he changed only a week later back to stock 2nd cats and exhaust cause he got tired of the rotten egg smell.

i hope you kept your stock exhaust pieces !!
.

Panoz · 02-21-2009, 09:45 AM

there is no dumpest & unethical thing than removing all the cats

BMWdmk · 02-21-2009, 12:58 PM

i had catless downpipes and AA exhaust
smell went away after a week or two

maybe an adaptation thing?
would the ecu adjust in any way to this mod?
that might be the case

BALLAJL15 · 02-21-2009, 02:02 PM

Quote:

Originally Posted by dmkaldas

i had catless downpipes and AA exhaust
smell went away after a week or two

maybe an adaptation thing?
would the ecu adjust in any way to this mod?
that might be the case

There is no adaptation for the secondary cats with the ecu... The smell is because of no cats simple as that... It smells like crap but to make the most hp you have to be fully catless.

02-20-2009, 12:22 AM	#1
Sam12345 Lieutenant Colonel 106 Rep 1,534 Posts Drives: jet black 335i coupe Join Date: Feb 2008 Location: So Cal iTrader: (3) Garage List 2008 335i Coupe [0.00]	Just removed 2nd cat and .... Ok, so i have Catless downpipes, JB3, and Aftermarket mufflers. The car sounded fine, and the only time the car ever smelled was during the cold start Today i went to a well known exhuast shop and had my 2nd cats removed Afterwords.... The car starts making a VERY LOUD rattling noise, around 2k RPM. Everytime i shift and it goes to 2k it makes the noise. I have to stay in high RPMs to avoid it. I suppose this is bad welding? Problem 2....the car smells so FUCKING BAD. when i am stopped and my car is idoling with windows open i completly smell it. I know it was going to smell worse, but come on i didnt think it would smell this bad. Could the extra smell be from a leak from the poor welding? Thanks guys __________________ Legal Disclaimer: Anything I or anyone else says about my vehicle on this website(e90post.com or any affiliated or nonaffiliated sites), pertaining to modifications, is only to gain acceptance from my/our peers, and does not actually represent anything actually existing on my car, and thus, cannot be held against me in any issues, i.e. warranty claims, that may arise.
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02-20-2009, 12:25 AM	#2
enrita Major General 161 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	think they did not a good job by removing the CAT . Go back to them and check . Could be leaking or something. __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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02-20-2009, 12:30 AM	#3
Bimmer Nerd Major General 519 Rep 7,789 Posts Drives: 6MT F80 Join Date: Jun 2008 Location: Santa Monica, CA iTrader: (12)	yea it might be poor welding and most likely its some kind of a leak.
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02-20-2009, 12:39 AM	#4
Sam12345 Lieutenant Colonel 106 Rep 1,534 Posts Drives: jet black 335i coupe Join Date: Feb 2008 Location: So Cal iTrader: (3) Garage List 2008 335i Coupe [0.00]	definatly going back tommorow, honestly i feel dizzy a bit from the fumes still. it was ridiculously smelly. __________________ Legal Disclaimer: Anything I or anyone else says about my vehicle on this website(e90post.com or any affiliated or nonaffiliated sites), pertaining to modifications, is only to gain acceptance from my/our peers, and does not actually represent anything actually existing on my car, and thus, cannot be held against me in any issues, i.e. warranty claims, that may arise.
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02-20-2009, 12:39 AM	#5
pdjafari Colonel 153 Rep 2,472 Posts Drives: G80 M3C Join Date: Oct 2007 Location: Earth iTrader: (5)	i always thought a ticking sound was a sign of an exhaust leak??
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02-20-2009, 12:52 AM	#6
addicted2drums Second Lieutenant 7 Rep 220 Posts Drives: e90 Join Date: Apr 2008 Location: California iTrader: (1)	I have seen several posts from people that have removed the second cats complaining about the smell, so i think that is normal for that mod.
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02-20-2009, 04:36 AM	#8
enrita Major General 161 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	Fully catless is in my opinion pretty bad. at least one set should be in. and for what ? 5 hp gain??? __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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02-20-2009, 09:14 PM	#11
Sam12345 Lieutenant Colonel 106 Rep 1,534 Posts Drives: jet black 335i coupe Join Date: Feb 2008 Location: So Cal iTrader: (3) Garage List 2008 335i Coupe [0.00]	ye guys, the noise was from a small leak. but regardless the car smelled SOO FUCKING BAD! i kid you not, i had my friend do a drive by for me, and i suffocated for a solid 30 seconds after he passed. You cannot roll your windows down unless cruising at 10mph+. fuck 2nd cat delete __________________ Legal Disclaimer: Anything I or anyone else says about my vehicle on this website(e90post.com or any affiliated or nonaffiliated sites), pertaining to modifications, is only to gain acceptance from my/our peers, and does not actually represent anything actually existing on my car, and thus, cannot be held against me in any issues, i.e. warranty claims, that may arise.
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02-20-2009, 09:18 PM	#12
E92White N54 Power Baby 29 Rep 680 Posts Drives: E82 135i SGM Join Date: Nov 2008 Location: Brownsville,TX iTrader: (3)	did you feel any difference in performance ?
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02-20-2009, 10:21 PM	#14
cn555ic 442 Rep 18,331 Posts Drives: 335i Join Date: Jun 2007 Location: US iTrader: (6)	Damn I wonder why guys that are completely catless don't ever say that the car has such a bad smell....I am thinking about it, but probably wait for the CPE catted ones!!! I would not want to be getting any headaches from the smell
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02-21-2009, 12:34 AM	#15
CaptChaos Captain 55 Rep 817 Posts Drives: 2017 M2 - Mineral Grey Join Date: Oct 2006 Location: Richmond, BC, Canada iTrader: (0)	What does it smell like?
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02-21-2009, 01:11 AM	#17
gian335 Major 37 Rep 1,031 Posts Drives: e92 335 Join Date: Apr 2008 Location: uknown iTrader: (1)	it smells pretty bad when its cold, when the car warms up its a little better. but u can still smell it when ur around the car when its on (idling).
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02-21-2009, 01:13 AM	#18
gian335 Major 37 Rep 1,031 Posts Drives: e92 335 Join Date: Apr 2008 Location: uknown iTrader: (1)	do the secondary cats tame down the smell a little bit, if u have catless downpipes?
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02-21-2009, 09:45 AM	#20
Panoz Lieutenant Colonel 84 Rep 1,575 Posts Drives: E92 Space Grey 335i ,Aero Kit Join Date: Nov 2006 Location: EU iTrader: (0)	there is no dumpest & unethical thing than removing all the cats __________________ Procede V4 , Catless DPs, Forge FMIC, Injen Intake, VK Oilcooler, Hartge Quads Exhaust, Modded CDV, Synapse BOV Kit, BMW Performance 335i SSK Kit, P3 vent boost gauge Space Grey 335i -> See more pics HERE
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02-21-2009, 12:58 PM	#21
BMWdmk Rollin 3rd 106 Rep 1,232 Posts Drives: Something fast Join Date: Sep 2007 Location: Chino Hills iTrader: (15)	i had catless downpipes and AA exhaust smell went away after a week or two maybe an adaptation thing? would the ecu adjust in any way to this mod? that might be the case
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