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
      11-16-2012, 10:00 AM   #1
SalemChiro
Second Lieutenant
3
Rep
264
Posts

 
Drives: 135i vert
Join Date: May 2012
Location: MA

iTrader: (0)

Crazy High AFR's

Hey guys,

I'm running COBB Stage 1+ Sport on 93 octane and data logged for the first time.

Everything looked good but the AFR shot into the 200's. After pulling codes, the LPFP comes up. Could this be causing the AFR issue? Should I revert back to stock tune for now?

I'm new to data logging and couldn't post the data here....

Thanks for any help.

Sean
Appreciate 0
      11-16-2012, 10:06 AM   #2
Stohlen
Major
18
Rep
1,228
Posts

 
Drives: AW 135i
Join Date: Aug 2012
Location: Waterford, Mi

iTrader: (2)

Garage List
2008 BMW 135i  [2.83]
200's????
Appreciate 0
      11-16-2012, 10:08 AM   #3
Tee-Dub
Captain
Tee-Dub's Avatar
United_States
11
Rep
753
Posts

 
Drives: 2008 135i
Join Date: May 2009
Location: Vancouver, WA

iTrader: (9)

I don't know what "200's" means. Could be an anomaly? Don't think the car would run. Have you sent your logs over to COBB, they're supposed to have excellent support.
Appreciate 0
      11-16-2012, 10:16 AM   #4
DRedman45
First Lieutenant
DRedman45's Avatar
4
Rep
392
Posts

 
Drives: 07 e86 //M coupe
Join Date: Oct 2012
Location: Northern va

iTrader: (0)

if the afr was 200:1 the motor would have blown apart, or melted rings from running that lean...put the stock tune on and log the afr...if that situation really occurred it would more likely be a component failure
Appreciate 0
      11-16-2012, 10:17 AM   #5
SalemChiro
Second Lieutenant
3
Rep
264
Posts

 
Drives: 135i vert
Join Date: May 2012
Location: MA

iTrader: (0)

This is what I could copy and paste.... I'll try to data log again today and see if it was an anomaly. The car feels like it runs fine, no hesitation or sputtering.

Lambda (Bank1) (AFR)
13.96
14.55
16.17
17.35
27.78
38.07
75.41
98.78
220.21
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
200.95
79.53
28.81
24.4
21.46
20.73
21.17
24.11
29.69
35.28
47.48
56.89
79.38
108.63
135.24
181.54
221.24
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
235.2
201.39
62.03
38.81
27.78
22.49
19.55
18.96
18.23
17.93
17.2
16.32
15.58
14.55
14.11
13.82
14.11
14.11
13.67
13.23
13.08
Appreciate 0
      11-16-2012, 10:31 AM   #6
Stohlen
Major
18
Rep
1,228
Posts

 
Drives: AW 135i
Join Date: Aug 2012
Location: Waterford, Mi

iTrader: (2)

Garage List
2008 BMW 135i  [2.83]
Somethings not right, lambda is measured based around 1. Where 1 is stoich.

Quote:
Originally Posted by DRedman45 View Post
if the afr was 200:1 the motor would have blown apart, or melted rings from running that lean..
No at that A/F it would have just shut off...
Appreciate 0
      11-16-2012, 10:47 AM   #7
SalemChiro
Second Lieutenant
3
Rep
264
Posts

 
Drives: 135i vert
Join Date: May 2012
Location: MA

iTrader: (0)

OK, thanks for the input. I sent the log to Cobb for viewing and I'll record new logs today with stock and stage1+ tune.
Appreciate 0
      11-16-2012, 10:54 AM   #8
c_ozanich
ENGINEER
c_ozanich's Avatar
United_States
7
Rep
499
Posts

 
Drives: '11 135i 6MT M-Pack
Join Date: Sep 2012
Location: Warren Ohio

iTrader: (0)

Quote:
Originally Posted by Stohlen View Post
Somethings not right, lambda is measured based around 1. Where 1 is stoich.



No at that A/F it would have just shut off...
that's correct. 14.7:1 is stoich for "perfect a/f ratio"

at 200:1 that's saying there are essentially 200 lbs of air to 1 pound of gas. There wouldn't be any mixture of gas and air to create fuel and it wouldn't ignite strong enough without super high pressure in your cylinders; meaning the engine would think there just isn't any gas at all, and shut off. You would be running ridiculously lean and it wouldn't even give the engine a chance to hurt itself by igniting full combustion.

Quote:
Originally Posted by SalemChiro View Post
OK, thanks for the input. I sent the log to Cobb for viewing and I'll record new logs today with stock and stage1+ tune.
sounds like a solid plan. keep us posted
Appreciate 0
      11-16-2012, 11:02 AM   #9
DRedman45
First Lieutenant
DRedman45's Avatar
4
Rep
392
Posts

 
Drives: 07 e86 //M coupe
Join Date: Oct 2012
Location: Northern va

iTrader: (0)

Quote:
Originally Posted by Stohlen View Post
No at that A/F it would have just shut off...
I am aware...but the op's car was still running...my point was there is something wrong other than the actual afr from the tune, because its not possible
Appreciate 0
      11-16-2012, 12:16 PM   #10
c_ozanich
ENGINEER
c_ozanich's Avatar
United_States
7
Rep
499
Posts

 
Drives: '11 135i 6MT M-Pack
Join Date: Sep 2012
Location: Warren Ohio

iTrader: (0)

Quote:
Originally Posted by DRedman45 View Post
I am aware...but the op's car was still running...my point was there is something wrong other than the actual afr from the tune, because its not possible
i wasn't meaning to be insulting in explaining, just making sure OP is on the same page as everyone and knows what he is doing with his car. You are correct that it isn't possible to sustain combustion with the given a/f ratio.

I bet it more has to do with an error in the data logging or in the tune itself provided the car stayed running and didn't fail in that sense.
Appreciate 0
      11-16-2012, 12:20 PM   #11
Freon
Captain
United_States
16
Rep
911
Posts

 
Drives: 2009 135i
Join Date: Nov 2007
Location: Indianapolis

iTrader: (2)

That is engine decel and nothing to worry about. When you let off the gas and coast with the transmission in gear, the engine turns off the injectors and you go "infinitely lean" because there is zero fuel. Loggers and sensors generally have an upper limit. It seems it is 235.2. Some stop at 22:1. My LM-1 sensor will actually read oxygen % on its display, but my gauge stops at around 22:1 IIRC.
__________________
2009 BMW 135i 6MT Sport, AFE intake, Cobb AP, Apex 18x8.5+9.5, 255/275 PSS
Appreciate 0
      11-16-2012, 12:23 PM   #12
b1aze
Just one more taste...
United_States
22
Rep
1,419
Posts

 
Drives: 2010 135i
Join Date: Aug 2012
Location: Shirley, MA

iTrader: (14)

Log the throttle position and line it up with AFR.
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
Forum Jump


All times are GMT -5. The time now is 11:07 PM.




1addicts
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
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