UR Catless DP's CEL or no CEL

Hallandale E92 · 10-31-2007, 09:27 PM

people who have the UR catless downpipes have you had a problem with the CEL coming on.

NYCGarbagePrince · 10-31-2007, 09:48 PM

It is catless... You are gonna get a CEL end of story.

sambonator · 10-31-2007, 10:08 PM

How do you prevent CEL's with catless DPs?

Evo8MRto335I · 10-31-2007, 10:13 PM

Quote:

Originally Posted by sambonator

How do you prevent CEL's with catless DPs?

You can get a mechanical fooler (looks like a spark plug insert)or electrical fooler(little small module).

Hallandale E92 · 10-31-2007, 10:20 PM

yea forget this thread i decided to F*** it im just going to get my DP's installed and stop being a Bitch lol once i get n xede i can go around it.

O-cha · 10-31-2007, 10:23 PM

Quote:

Originally Posted by NYCGarbagePrince

It is catless... You are gonna get a CEL end of story.

Tell that to all the people on this board with them installed?

NYCGarbagePrince · 10-31-2007, 10:38 PM

shell out the extra 350 or so for high flow cats. No CEL. Or try and extend the bungs.

ADHD · 10-31-2007, 10:41 PM

Quote:

Originally Posted by NYCGarbagePrince

shell out the extra 350 or so for high flow cats. No CEL. Or try and extend the bungs.

well catless will get u more power flat out!!! There is peeps with the catless that dont have cel's so im sure its a win lose situation!
Either way ive got my CAtless coated dp's in route!!

Walked U · 10-31-2007, 11:49 PM

Ive had catless and catted no cels from either one.

ADHD · 11-01-2007, 11:00 AM

Quote:

Originally Posted by Walked U

Ive had catless and catted no cels from either one.

EXACTLY thanks for chiming in bud!!

turbotko · 11-01-2007, 11:05 AM

You will get a CEL sooner or later depending on when the car is allowed to complete the OBD 2 drive cycles needed to run the catalyst monitor. You guys running catless DP's without a CE light must be driving the car in a way that doesn't allow the necessary drive cycles to run the catalyst monitor.

For example, without cats on my 04 mustang cobra (the catalyst monitor works the same on all OBD 2 cars BTW) I was able to go 6-8 months without a CE light on. The reason was because I usually only drove the car 4 miles back and forth to work and beat the snot out of it the whole time. I finally got a CE light while on a long road trip with the car........it finally was allowed the 2 complete drive cycles required to run the catalyst monitor and turn the CEL on.

As far as my research shows (I'm a BMW master tech so I have access to some pretty reliable sources

) the post cat 02 sensors are just regular old 0-1.0 volt 02 sensors, in which case the readily available 02 sensor simulators (check the mustang magazines, they're sold all over the place) should do the trick once the connectors were swapped to plug into the factory BMW harness.

Bottom line, without cats you WILL sooner or later get a CEL, after all that is the ONLY point in having post cat O2 sensors from the factory

DrewKo · 11-01-2007, 12:47 PM

Quote:

Originally Posted by turbotko

You will get a CEL sooner or later depending on when the car is allowed to complete the OBD 2 drive cycles needed to run the catalyst monitor. You guys running catless DP's without a CE light must be driving the car in a way that doesn't allow the necessary drive cycles to run the catalyst monitor.

For example, without cats on my 04 mustang cobra (the catalyst monitor works the same on all OBD 2 cars BTW) I was able to go 6-8 months without a CE light on. The reason was because I usually only drove the car 4 miles back and forth to work and beat the snot out of it the whole time. I finally got a CE light while on a long road trip with the car........it finally was allowed the 2 complete drive cycles required to run the catalyst monitor and turn the CEL on.

As far as my research shows (I'm a BMW master tech so I have access to some pretty reliable sources

) the post cat 02 sensors are just regular old 0-1.0 volt 02 sensors, in which case the readily available 02 sensor simulators (check the mustang magazines, they're sold all over the place) should do the trick once the connectors were swapped to plug into the factory BMW harness.

Bottom line, without cats you WILL sooner or later get a CEL, after all that is the ONLY point in having post cat O2 sensors from the factory

Dumb question, but will you get a CEL with catted DPs? Also, what area of GA are in? Tx.

scalbert · 11-01-2007, 01:19 PM

Quote:

Originally Posted by DrewKo

Dumb question, but will you get a CEL with catted DPs? Also, what area of GA are in? Tx.

No, you should not trip any codes with functioning catalytic converters.

Hopefully he lives in the Atlanta area and has access to and like to share vehicle specific tools.

purplewidow · 11-01-2007, 01:42 PM

why the hell would someone come out with a product that causes cels/codes to pop....wtf i mean only procede, these dp's, and a ton of others have thrown codes...i also see a lot of people just buying cause they want performance now instead of waiting and seeing more reliable products.....

scalbert · 11-01-2007, 01:45 PM

Quote:

Originally Posted by purplewidow

i also see a lot of people just buying cause they want performance now instead of waiting and seeing more reliable products.....

It has nothing to do with the downpipes being reliable. The removal of the catalytic converters is the culprit in this discussion. I would assume that the downpipe manufacturers also state the catless versions are for offroad use only. The unfortunate aspect is that many will shell out $$ without knowing what they are getting.

turbotko · 11-01-2007, 03:29 PM

Quote:

Originally Posted by scalbert

Hopefully he lives in the Atlanta area and has access to and like to share vehicle specific tools.

We'll just keep to GA right now. Do to my profession I must be very very careful about what I say on these forums. Big Brother is always watching and I really don't need to advertise exactly which dealer I work for. You guys can PM though if you have any questions that I cannot answer here for you.

scalbert · 11-01-2007, 03:34 PM

Quote:

Originally Posted by turbotko

We'll just keep to GA right now. Do to my profession I must be very very careful about what I say on these forums. Big Brother is always watching and I really don't need to advertise exactly which dealer I work for. You guys can PM though if you have any questions that I cannot answer here for you.

Understood...

orientblue3 · 11-01-2007, 03:40 PM

Quote:

Originally Posted by turbotko

You will get a CEL sooner or later depending on when the car is allowed to complete the OBD 2 drive cycles needed to run the catalyst monitor. You guys running catless DP's without a CE light must be driving the car in a way that doesn't allow the necessary drive cycles to run the catalyst monitor.

For example, without cats on my 04 mustang cobra (the catalyst monitor works the same on all OBD 2 cars BTW) I was able to go 6-8 months without a CE light on. The reason was because I usually only drove the car 4 miles back and forth to work and beat the snot out of it the whole time. I finally got a CE light while on a long road trip with the car........it finally was allowed the 2 complete drive cycles required to run the catalyst monitor and turn the CEL on.

As far as my research shows (I'm a BMW master tech so I have access to some pretty reliable sources

) the post cat 02 sensors are just regular old 0-1.0 volt 02 sensors, in which case the readily available 02 sensor simulators (check the mustang magazines, they're sold all over the place) should do the trick once the connectors were swapped to plug into the factory BMW harness.

Bottom line, without cats you WILL sooner or later get a CEL, after all that is the ONLY point in having post cat O2 sensors from the factory

So 02 sensor simulators won't be effective on catless DP's? I believe there was one vendor who supplied them with their DP's so that's why I ask.

leftcoastman · 11-01-2007, 06:15 PM

The recently released DME update from BMW will cause everyone's car to CEL when you put on the catless.

The reason why they have a pre and post cat O2 is to determine whether the O2 levels are dropping post cat - in other words, if the cat is doing its job.

I chose the catted version because well, I'm ok with 30 instead of 35 hp increase.

turbotko · 11-02-2007, 01:09 PM

Quote:

Originally Posted by orientblue3

So 02 sensor simulators won't be effective on catless DP's? I believe there was one vendor who supplied them with their DP's so that's why I ask.

Yes O2 sims should take care of the problem although I haven't tried them personally. You'll have to swap the connectors from your original post cat O2's over to the O2 sims.

NYCGarbagePrince · 11-02-2007, 01:16 PM

Quote:

Originally Posted by Walked U

Ive had catless and catted no cels from either one.

Oh my god. Walkedu I appreciate everything you add to this board. But on this topic you have begun to really bother me. Explain to everyone WHY your car does not get CELs. He extended his bungs when fabricating his DP's. I run UR Downpipes. If you run UR downpipes without cats you WILL get a CEL. Everyone I have ever met without cats in their downpipe HAS A CEL. All you are doing by telling people you have DP's and dont have a CEL without explaining is making them believe they have a chance that if they buy a catless DP they won't have a CEL. In my eyes that is a disservice.

ADHD · 11-02-2007, 01:28 PM

Quote:

Originally Posted by NYCGarbagePrince

Oh my god. Walkedu I appreciate everything you add to this board. But on this topic you have begun to really bother me. Explain to everyone WHY your car does not get CELs. He extended his bungs when fabricating his DP's. I run UR Downpipes. If you run UR downpipes without cats you WILL get a CEL. Everyone I have ever met without cats in their downpipe HAS A CEL. All you are doing by telling people you have DP's and dont have a CEL without explaining is making them believe they have a chance that if they buy a catless DP they won't have a CEL. In my eyes that is a disservice.

So your saying hes running a fix??? Either way thers lots of info just on this thread that im sure we could figure out a fix

View Poll Results: CEL ??
No problem wih CEL	4	26.67%
CEL light has come on	11	73.33%
Voters: 15. You may not vote on this poll

10-31-2007, 09:27 PM	#1
Hallandale E92 Lieutenant 36 Rep 587 Posts Drives: 2007 335i Titanium Silver Join Date: Apr 2007 Location: Hallandale, Florida iTrader: (2)	UR Catless DP's CEL or no CEL people who have the UR catless downpipes have you had a problem with the CEL coming on. __________________ ON Order: Crimson on Coral E92 335i RIP: Totaled 2007 335i Titanium Silver/ Coral Red : VIP Tuning Custom tune, VIP Tuning Intake, VIP Tuning charge pipes, VIP Tuning BOV, UR cat-less down pipes, OEM aero lip, OEM aero rear valence, 19" Iforged Daytonas
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10-31-2007, 09:48 PM	#2
NYCGarbagePrince Major 256 Rep 1,435 Posts Drives: X6 50i Join Date: Aug 2007 Location: NYC iTrader: (0)	It is catless... You are gonna get a CEL end of story.
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10-31-2007, 10:08 PM	#3
sambonator Samtaro! 128 Rep 2,609 Posts Drives: 2014 F32 N55 Alpinweiß Join Date: May 2007 Location: Newport Beach, CA, USA iTrader: (7)	How do you prevent CEL's with catless DPs? __________________
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10-31-2007, 10:20 PM	#5
Hallandale E92 Lieutenant 36 Rep 587 Posts Drives: 2007 335i Titanium Silver Join Date: Apr 2007 Location: Hallandale, Florida iTrader: (2)	yea forget this thread i decided to F*** it im just going to get my DP's installed and stop being a Bitch lol once i get n xede i can go around it. __________________ ON Order: Crimson on Coral E92 335i RIP: Totaled 2007 335i Titanium Silver/ Coral Red : VIP Tuning Custom tune, VIP Tuning Intake, VIP Tuning charge pipes, VIP Tuning BOV, UR cat-less down pipes, OEM aero lip, OEM aero rear valence, 19" Iforged Daytonas
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10-31-2007, 10:38 PM	#7
NYCGarbagePrince Major 256 Rep 1,435 Posts Drives: X6 50i Join Date: Aug 2007 Location: NYC iTrader: (0)	shell out the extra 350 or so for high flow cats. No CEL. Or try and extend the bungs.
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10-31-2007, 11:49 PM	#9
Walked U Brigadier General 186 Rep 3,125 Posts Drives: Too many to list Join Date: Nov 2006 Location: USA iTrader: (5)	Ive had catless and catted no cels from either one. __________________ Previous - E90 335i, E82 135i, E89 Z4 3.5SI, Range Rover S/C, Ultra White RCF, Maserati Granturismo Current Lexus: SMG LC500 performance package Porsche:1973 911E Ferrari 575 SA, 458 Italia
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11-01-2007, 11:05 AM	#11
turbotko Lieutenant 67 Rep 527 Posts Drives: 09 E90 M3 Join Date: May 2007 Location: georgia iTrader: (3)	You will get a CEL sooner or later depending on when the car is allowed to complete the OBD 2 drive cycles needed to run the catalyst monitor. You guys running catless DP's without a CE light must be driving the car in a way that doesn't allow the necessary drive cycles to run the catalyst monitor. For example, without cats on my 04 mustang cobra (the catalyst monitor works the same on all OBD 2 cars BTW) I was able to go 6-8 months without a CE light on. The reason was because I usually only drove the car 4 miles back and forth to work and beat the snot out of it the whole time. I finally got a CE light while on a long road trip with the car........it finally was allowed the 2 complete drive cycles required to run the catalyst monitor and turn the CEL on. As far as my research shows (I'm a BMW master tech so I have access to some pretty reliable sources ) the post cat 02 sensors are just regular old 0-1.0 volt 02 sensors, in which case the readily available 02 sensor simulators (check the mustang magazines, they're sold all over the place) should do the trick once the connectors were swapped to plug into the factory BMW harness. Bottom line, without cats you WILL sooner or later get a CEL, after all that is the ONLY point in having post cat O2 sensors from the factory __________________ 10 AW on fox E90 M3 with 2 pedals, gentleman’s ride 08 AW on fox E92 M3 also 2 pedals, a bit more rowdy
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11-01-2007, 01:42 PM	#14
purplewidow Lieutenant Colonel 51 Rep 1,928 Posts Drives: e92 335 Join Date: Feb 2007 Location: Chicago iTrader: (2)	why the hell would someone come out with a product that causes cels/codes to pop....wtf i mean only procede, these dp's, and a ton of others have thrown codes...i also see a lot of people just buying cause they want performance now instead of waiting and seeing more reliable products.....
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11-01-2007, 06:15 PM	#19
leftcoastman Lieutenant Colonel 55 Rep 1,714 Posts Drives: 335i Join Date: Jan 2007 Location: Near some canyons iTrader: (1)	The recently released DME update from BMW will cause everyone's car to CEL when you put on the catless. The reason why they have a pre and post cat O2 is to determine whether the O2 levels are dropping post cat - in other words, if the cat is doing its job. I chose the catted version because well, I'm ok with 30 instead of 35 hp increase.
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