BMW 1 Series Coupe Forum / 1 Series Convertible Forum (1M / tii / 135i / 128i / Coupe / Cabrio / Hatchback) (BMW E82 E88 128i 130i 135i)
 





 

Post Reply
 
Thread Tools Search this Thread
      09-07-2011, 01:39 PM   #1
Juicehead
Lieutenant
99
Rep
561
Posts

Drives: Raptor
Join Date: Sep 2010
Location: Tampa, FL

iTrader: (3)

Figure this one out, Weird exhaust note change...

I am FBO with a Cobb AP Stage 1 Tune. I can be just cruising along and suddenly the exhaust note will change (get louder). The car does seem to accelerate a tiny bit as well (hardly noticeable).

Could this just be a fuel mapping issue with the tune, or perhaps the ECU is not getting the correct feedback from the O2 sensors in the downpipes even?

I am out of ideas of what it may be.
Appreciate 0
      09-07-2011, 03:35 PM   #2
akak1997
Major
akak1997's Avatar
62
Rep
1,159
Posts

Drives: BMW 135 @ 135mph
Join Date: Aug 2008
Location: Los Angeles

iTrader: (2)

Garage List
2008 135i  [0.00]
stock exhaust? could just be the exhaust flap opening up.
Appreciate 0
      09-07-2011, 04:10 PM   #3
Kcc
First Lieutenant
Kcc's Avatar
Canada
9
Rep
373
Posts

Drives: 4 Wheels with a turbo
Join Date: Jul 2010
Location: Markham, Toronto

iTrader: (0)

Flap opens up at 1.1k RPM, so I don't think that's the case.

Maybe non even road? Little hill up or down will affect the boost.

Kcc
__________________
135i - AW
Appreciate 0
      09-07-2011, 04:13 PM   #4
dfv2
Lieutenant
dfv2's Avatar
United_States
30
Rep
474
Posts

Drives: 2009 CTS-V
Join Date: Apr 2010
Location: Upstate NY

iTrader: (3)

same thing here, I assume cam angle...
__________________
//ecg//
Appreciate 0
      09-07-2011, 05:38 PM   #5
Juicehead
Lieutenant
99
Rep
561
Posts

Drives: Raptor
Join Date: Sep 2010
Location: Tampa, FL

iTrader: (3)

catless DPS and full berk exhaust...

no flippity flap!
Appreciate 0
      09-07-2011, 06:09 PM   #6
Das Ein
Captain
Das Ein's Avatar
United_States
30
Rep
815
Posts

Drives: '16 Audi TTS, '17 500 Abarth
Join Date: Aug 2008
Location: The Colony, TX

iTrader: (4)

Its the wastegate opening. Mine does it too.
Appreciate 0
      09-07-2011, 06:57 PM   #7
Eyeman
Colonel
Eyeman's Avatar
119
Rep
2,033
Posts

Drives: 2008 135 blk, blk, step
Join Date: Jan 2009
Location: Atlanta, GA

iTrader: (0)

Garage List
Yup, the sound from my car varies pretty heavily. Most noticeable to me is how much louder it first idles when coming off a highway cruise.
__________________
Injen, RR OCC, MadDad Whisper, donut spare, 19x8.5et43fr 19x9.5et45r Volk LE37's, rear fenders rolled/pulled, PSS4S 225/35fr 255/30r, KW V1's, AR coated catless dps, Cross strutbar, CF grills and license plate holder, iCarbon diffuser, ETS black anodized FMIC, M3 control arms, Quaife, ER chargepipe, ForgeDV's, Topspeed Custom Tune, V3sims, Braille, Andrey_GTA rear hub mod, Ebay Mstyle front bumper and performance style side skirts.
Appreciate 0
      09-08-2011, 11:43 AM   #8
baylor1er
Sic 'Em Bears
baylor1er's Avatar
4
Rep
99
Posts

Drives: 135i coupe Blk on Blk
Join Date: Mar 2010
Location: Waco/Houston, TX

iTrader: (0)

Its def. the wastegate. Mine does this all the time at a 70mph cruise. I have strait pipes and it is super noticable. I'm so used to it that I don't pay attention to it anymore.
__________________

6AT/Sport Package; BMS JB4 Map5; Custom Exhaust; Eibach Pro Street Springs
http://www.youtube.com/watch?v=-xNzG9ghq3s
http://www.youtube.com/watch?v=NgL7yTJOd0c
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -5. The time now is 05:32 AM.




1addicts
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST