BMW M3 Forum
BMW M3 Forum BMW M3 Gallery BMW M3 Reviews BMW M3 Social Groups BMW M3 Chat M3Forum Sponsors >>
Loading


Mobile M3forum
Go Back   BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X) > BMW M3 Discussions > E46 M3 (2001-2006)
Tire Rack Buy Winter Tires Now!
Not a member? Register Now!
Register Gallery All Albums Garage Search Today's Posts Mark Forums Read Calendar FAQ

E46 M3 (2001-2006) Engine: S54 - Max Hp: 333 hp at 7,900 rpm / 262 lb/ft at 4,900 rpm
Total Produced: 45,000+ - Years Produced: 2001 to 2006.


Reply
 
Thread Tools Display Modes
Old Fri, Dec-11-2009, 01:56:37 AM   #1
achtungM3
Registered User
 
achtungM3's Avatar
 
Join Date: Oct 2006
Posts: 275
Reputation: 0 achtungM3 is on a distinguished road
Location: fort collins

United States




Default euro headers no cats...

i just installed euro headers with oem section 1 and stebro muffler. wow! crazy loud. i am for sure going to put a resonated section 1 in a some point.
my question is, i took it out for a test drive and it is kind of lurchy and hit and miss. kind of like catching on all cylinders and then not firing on all cylinders. of course the ses light came on. is the computer relearning since i dont have the post cat sensors or the egt sensor hooked up?
thanks...
Jump to top achtungM3 is offline   Reply With Quote
Sponsored Links
Register now and remove these ads
Old Fri, Dec-11-2009, 02:56:57 AM   #2
uniqueM3
Registered User
 
uniqueM3's Avatar
 
Join Date: Apr 2009
Posts: 223
In the garage:
Reputation: 0 uniqueM3 is on a distinguished road
Location: el monte

United States




Default

You need to get software of course. Cross ur fingers and hope that fixes the problem cause it sure didn't for me. I installed the supersprint stepped headers with the oversized section 1 with no cats. SES light came on and felt what ur feeling. Took the car to get the software done and ses light still came back on. Got a obd readers and I have a missfire in 3 cylinders and a vaccume leak. Changed the spark plugs and coils and problem still there. Hopefully your ///M3 doesn't go through what mine is going through. Goodluck
Jump to top uniqueM3 is offline   Reply With Quote
Old Fri, Dec-11-2009, 03:55:49 PM   #3
EricSMG
40 something
 
Join Date: Nov 2008
Posts: 11,057
Reputation: 0 EricSMG is on a distinguished road
Location: San Diego

United States




Default

I drove my car like that for a couple weeks (no software) and it ran great. More power than stock, for sure, but not super smooth. Once I got software, there was even more power and it pulled smooth all the way.
__________________

Current - 2017 F82 M4 ZCP DCT Blk/Blk Fully Loaded
Current - 2004 E46 M3 6MT SG/Black
Sold - 2018 F80 M3 ZCP 6MT AW/Black Cloth "stripper"
Jump to top EricSMG is offline   Reply With Quote
Old Sat, Dec-12-2009, 05:33:04 AM   #4
MEM3
Registered User
 
Join Date: Feb 2009
Posts: 215
Reputation: 0 MEM3 is on a distinguished road

United States




Default

i think you guys switched your 02 sensors when your headers
Jump to top MEM3 is offline   Reply With Quote
Old Sat, Dec-12-2009, 05:45:49 AM   #5
achtungM3
Registered User
 
achtungM3's Avatar
 
Join Date: Oct 2006
Posts: 275
Reputation: 0 achtungM3 is on a distinguished road
Location: fort collins

United States




Default

i think so too. i drove the car again tonight after work and same results. i am trying to find info on which two sensors i should leave in and which header they need to be in.
Jump to top achtungM3 is offline   Reply With Quote
Old Sun, Dec-13-2009, 04:23:38 PM   #6
EricSMG
40 something
 
Join Date: Nov 2008
Posts: 11,057
Reputation: 0 EricSMG is on a distinguished road
Location: San Diego

United States




Default

Quote:
Originally Posted by achtungM3 View Post
i think so too. i drove the car again tonight after work and same results. i am trying to find info on which two sensors i should leave in and which header they need to be in.
Hmmm.... you'll need to search (or ask someone to post up) for the picture of the 02 routing under the hood and go from there. I remember it was a bit confusing to keep track of them.

That said, my headers have a spot for all 4 02s AND an EGT port... so I didn't actually remove/alter anything. Car ran good. Euro headers only have 2 02 bungs as the rears are meant to be installed into the Euro section 1 (after the cats.) I'm not sure about the EGT either. You might need to get a couple bungs welded into your stock sec 1 and reinstall your rear 02s and then get software...... because I think most software requires all 4 O2s..... I know mine does.
__________________

Current - 2017 F82 M4 ZCP DCT Blk/Blk Fully Loaded
Current - 2004 E46 M3 6MT SG/Black
Sold - 2018 F80 M3 ZCP 6MT AW/Black Cloth "stripper"
Jump to top EricSMG is offline   Reply With Quote
Old Mon, Dec-14-2009, 12:12:49 AM   #7
achtungM3
Registered User
 
achtungM3's Avatar
 
Join Date: Oct 2006
Posts: 275
Reputation: 0 achtungM3 is on a distinguished road
Location: fort collins

United States




Default

tomorrow i will get it on a lift and swap the o2 sensors. i will let you guys know the results. thanks for all your help
Jump to top achtungM3 is offline   Reply With Quote
Old Mon, Dec-14-2009, 09:52:39 PM   #8
achtungM3
Registered User
 
achtungM3's Avatar
 
Join Date: Oct 2006
Posts: 275
Reputation: 0 achtungM3 is on a distinguished road
Location: fort collins

United States




Default

i checked today and i have the o2 sensor plugged in the right headers. the miss firing is hit and miss still. when it smoothes out the car runs really great. i am thinking i have a bad o2 sensor.
also i am thinking of just getting the custom performance innovations crt section 1, which will have post cat bungs. i wonder if i can get them to weld in a bung for my egt sensor?
Jump to top achtungM3 is offline   Reply With Quote
Old Wed, Dec-16-2009, 03:09:17 PM   #9
Donovan
Banned
 
Join Date: Jun 2007
Posts: 1,728
Reputation: 0 Donovan is on a distinguished road
Location: D.C. , Germany

United States




Default

Quote:
Originally Posted by EricSMG View Post
Hmmm.... you'll need to search (or ask someone to post up) for the picture of the 02 routing under the hood and go from there. I remember it was a bit confusing to keep track of them.

That said, my headers have a spot for all 4 02s AND an EGT port... so I didn't actually remove/alter anything. Car ran good. Euro headers only have 2 02 bungs as the rears are meant to be installed into the Euro section 1 (after the cats.) I'm not sure about the EGT either. You might need to get a couple bungs welded into your stock sec 1 and reinstall your rear 02s and then get software...... because I think most software requires all 4 O2s..... I know mine does.
Well..things are never easy. I dont have my personal welder machine here in my garage so I guess this will be a shop job...
Jump to top Donovan is offline   Reply With Quote
Old Thu, Dec-17-2009, 12:55:36 AM   #10
achtungM3
Registered User
 
achtungM3's Avatar
 
Join Date: Oct 2006
Posts: 275
Reputation: 0 achtungM3 is on a distinguished road
Location: fort collins

United States




Default finally!

alright instead of just visually checking my o2 sensors, i jacked the car up crawled underneath and swapped them around and that was the problem. runs great now!
no lean codes no misfire codes. just egt and post o2 codes and that is expected since i dont have those hooked up.
time for ess software now.
car pulls really well on the mid and top now. sounds better now that everything is hooked up right.
Jump to top achtungM3 is offline   Reply With Quote
Reply

Bookmarks

Tags
cats, euro, headers

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT. The time now is 02:44:40 AM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
M3Forum.com and M3forum.net is in no way sponsored, endorsed or affiliated by or with BMW NA / BMW AG or any of it's subsidiaries or vendors.
BMW and M3 (E90 M3 | E92 M3 | E93 M3 | E46 M3 | E36 M3 | E30 M3) are registered trademarks of BMW AG.
M3Forum Terms of Service
Copyright 1999-2017 M3Forum.com
Discussing euro headers no cats... in the E46 M3 (2001-2006) Forum - Engine: S54 - Max Hp: 333 hp at 7,900 rpm / 262 lb/ft at 4,900 rpm
Total Produced: 45,000+ - Years Produced: 2001 to 2006. at BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X)