# Few catalytic converter questions **URL:** \ **Category:** NYSpeed Automotive\ **Created:** [July 23, 2014, 2:28pm UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121 "2014-07-23T14:28:52Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![llink78](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/llink78/32/8037_2.png) [@llink78](https://forums.speedlife.net/u/llink78)\ **Post date:** [July 23, 2014, 2:28pm UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/1 "2014-07-23T14:28:52Z")
Last year i deleted the cats from my bmw for better flow. I love not having them. But i have not been able to get inspected. Tried flashing to Euro software, tried o2 sims. Did not try spark plug de fowlers but i hear they are the least reliable. I have a single 3" exhaust. What i am looking is for the option to swap in a cat after the headers where the pipe merges into the 3", and swap it back out to just a pipe after inspection every year with V clamps. Guess what i am asking is help choosing a catalytic converter that will keep my SES light off to pass emissions. And someone to cut the pipes, weld o2 bungs and weld the v clamps on @**[turbociv](http://www.nyspeed.com/member.php?u=386)** šŸ˜‰ and extend the o2 wires. ---
**Author:** ![livin4hockey](https://avatars.discourse-cdn.com/v4/letter/l/d2c977/32.png) [@livin4hockey](https://forums.speedlife.net/u/livin4hockey)\ **Post date:** [July 23, 2014, 3:47pm UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/2 "2014-07-23T15:47:53Z")
I canā€™t speak for the BMW side of things but I had a CEL on for a code that often people often attribute to a clogged cat on Corolla. Went the anti-fouler route on the 02 sensor and havenā€™t had the light come back in 10k+ miles driving with it. I know your situation is different and youā€™ve probably researched the defouler method a ton but figured I would share my experience. ---
**Author:** ![llink78](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/llink78/32/8037_2.png) [@llink78](https://forums.speedlife.net/u/llink78)\ **Post date:** [July 23, 2014, 4:07pm UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/3 "2014-07-23T16:07:36Z")
Yea the bmw dme is very touchy when it comes to emissions ā˜¹ that method has worked for maybe 10% of the people depending on car model and which update is being used. ---
**Author:** ![pirite](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/pirite/32/5308_2.png) [@pirite](https://forums.speedlife.net/u/pirite)\ **Post date:** [July 23, 2014, 10:12pm UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/4 "2014-07-23T22:12:02Z")
iā€™ve got two ā€œspacersā€ on my rear O2 sensor and havent had a singe issue at all. but honestly, if you donā€™t have the stock converter youā€™re going to be spending quite a bit of coin to find a converter that will actually do itā€™s just up to the specs of the BMWs specs in the ECU. ---
**Author:** ![Norb\_O](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/norb_o/32/5189_2.png) [@Norb\_O](https://forums.speedlife.net/u/Norb_O)\ **Post date:** [July 24, 2014, 5:39am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/5 "2014-07-24T05:39:46Z")
Does spacing out the 2nd O2 sensor witih spark plug anti foulers work? I did that on my catless Spec V and it worked fine, itā€™s even working now on my fianceā€™s B7 A4 (using 2 of them stacked). Wonā€™t know until you try Tom Besides your usual Pep Boys spark plug fouler there are nicer options > **[O2 Sensor Spacer](http://www.42draftdesigns.com/o2-sensor-spacer/)** > > High performance parts made in the USA including exhaust systems, air intake systems, wheel spacers, wheel adapters, oil catch cans, and more. They also have spacers that actually have a catalyst substrate inside them although I have no experience with these so I have no clue if they are effective. > **[O2 Sensor Tester](http://www.g-werke.com/exhaust-accessories/o2-sensor-tester/)** > > Milltek Sport Exhaust North American / U.S. Authorized largest stocking distributor/importer for Milltek Sport Catback Exhaust and downpipes, Recaro racing seats, as well as Stoptech Brakes, Scroth Racing seatbelts, Piloti shoes, and BBS wheels. The last option is to find someone who is parting out a car like yours or has ditched their cats to go with a race style exhaust and buy the catted portion on the cheap. Then swap it out come inspection time, but like you said, thatā€™s a pain ---
**Author:** ![ultradriver10000](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ultradriver10000/32/7397_2.png) [@ultradriver10000](https://forums.speedlife.net/u/ultradriver10000)\ **Post date:** [July 24, 2014, 5:41am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/6 "2014-07-24T05:41:47Z")
Iā€™d try to find a factory one on ebay or something cheap. ---
**Author:** ![Norb\_O](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/norb_o/32/5189_2.png) [@Norb\_O](https://forums.speedlife.net/u/Norb_O)\ **Post date:** [July 24, 2014, 5:48am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/7 "2014-07-24T05:48:02Z")
[http://forums.bimmerforums.com/forum/showthread.php?2105281-Partout-2001-330i-5spd](http://forums.bimmerforums.com/forum/showthread.php?2105281-Partout-2001-330i-5spd) ---
**Author:** ![IanK](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/iank/32/5016_2.png) [@IanK](https://forums.speedlife.net/u/IanK)\ **Post date:** [July 24, 2014, 7:01am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/8 "2014-07-24T07:01:09Z")
Shame they havenā€™t really cracked the open DME tuning on these yet, my car runs with zero cats, no CEL, forced ready. ---
**Author:** ![llink78](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/llink78/32/8037_2.png) [@llink78](https://forums.speedlife.net/u/llink78)\ **Post date:** [July 24, 2014, 7:06am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/9 "2014-07-24T07:06:15Z")
It sucks bc factory Cats in the e46 are build into the headers ā˜¹ So if i am to ever put one back onto the car it will be V-banded in right after the merge from both headers. maybe WE can try the spark plug fowler @Norb_O šŸ™‚ - - - Updated - - - > [@Norb O](#): > > [E46 Partout: 2001 330i 5spd.](http://forums.bimmerforums.com/forum/showthread.php?2105281-Partout-2001-330i-5spd) Again i have the stock headers. Not looking to go through 6 hours of hell once a year. - - - Updated - - - > [@IanK](#): > > Shame they havenā€™t really cracked the open DME tuning on these yet, my car runs with zero cats, no CEL, forced ready. I am going to try to get it inspected again soon, havenā€™t tried since using EU2. Just have to find an ā€œINā€. ---
**Author:** ![Norb\_O](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/norb_o/32/5189_2.png) [@Norb\_O](https://forums.speedlife.net/u/Norb_O)\ **Post date:** [July 24, 2014, 7:26am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/10 "2014-07-24T07:26:44Z")
Buy 2 anti foulers, bring it over and we will throw it in. While working on yours I saw a bunch of wire loom, followed it to the open compartment on the pass side, and saw the oxygen sensors thereā€¦I was like WTF! ---
**Author:** ![llink78](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/llink78/32/8037_2.png) [@llink78](https://forums.speedlife.net/u/llink78)\ **Post date:** [July 24, 2014, 9:28am UTC](https://forums.speedlife.net/t/few-catalytic-converter-questions/270121/11 "2014-07-24T09:28:02Z")
> [@Norb O](#): > > Buy 2 anti foulers, bring it over and we will throw it in. While working on yours I saw a bunch of wire loom, followed it to the open compartment on the pass side, and saw the oxygen sensors thereā€¦I was like WTF! Yea tried O2 sims. We could never get the Voltage right for the dme to think everything was OK.