Home Forums Articles How To's FAQ Register
Go Back   Xoutpost.com > BMW SAV Forums > X5 (E53) Forum
Fluid Motor Union
User Name
Password
Member List Premier Membership Search Today's Posts Mark Forums Read

Xoutpost server transfer and maintenance is occurring....
Xoutpost is currently undergoing a planned server migration.... stay tuned for new developments.... sincerely, the management


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 04-02-2019, 08:18 PM
Member
 
Join Date: Jul 2016
Location: Menlo Park, CA
Posts: 2,311
Fifty150hs is on a distinguished road
DME: Trimming, oxygen sensor before cat., Bank 2

After searching the forum and having found numerous threads about it, I'm totally confused. I hope someone can help me with this. I have a 2006 3.0 that just started throwing the code above. I've cleared it a couple times and it comes back. So I opened up the OBDII and got the live data. The live data is below. I hope someone can tell me what I'm seeing.

Load PCT: 5.5%
ECT: 203F
SHRTFT 1: varied between -1.6 to -3.1%
LONGFT 1: 6.3%
SHRTFT 2: varied between 0 to -3.9%
LONGFT 2: 7.0%
RPM: varied 774 to 781
Spark Adv: varied -2.5 to -3.5
IAT: 151F
MAF: .01lbs/s (calculates to 4.54 grams)
TP: 9.8%
O2B1S1: varied .130 to .730V
SHRTFTB1S1: varied -1.6% to -3.1%
O2B1S2: varied .750 to .770V
SHRTFTB1S2: 99.2%
O2B2S1: varied -.135 to .750V
SHRTFTB2S1: varied 0 to -3.1%
O2B2S2: varied .720 to .750V
SHRTFTB2S2: 99.2%

Thanks for any help you guys can provide. I'm not even sure where to start.
Reply With Quote

Sponsored Links

  #2  
Old 04-02-2019, 09:42 PM
andrewwynn's Avatar
Member
 
Join Date: Jun 2015
Location: Racine, WI
Posts: 10,818
andrewwynn will become famous soon enough
O2 can't range to negative values. The precat if reading negative values something is wrong. Looks like a case of problem sensor.

Also: post cat should gravitate to 0.45V so the 0.75 is very high but that can vary a lot.

What I would do: reset all the sensors by unplug them all, start the car run until you get multiple errors (probably missing O2 heater error) then plug them back in and clear the codes.

See if the numbers will come back into normal range (0.1 to 0.9v).

If you get values outside of normal you probably need to replace the sensor (use OE or OEM don't cheap out: I need to replace my knock off sensors)
__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)
Reply With Quote
  #3  
Old 04-02-2019, 10:23 PM
Member
 
Join Date: Jul 2016
Location: Menlo Park, CA
Posts: 2,311
Fifty150hs is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
O2 can't range to negative values. The precat if reading negative values something is wrong. Looks like a case of problem sensor.

Also: post cat should gravitate to 0.45V so the 0.75 is very high but that can vary a lot.

What I would do: reset all the sensors by unplug them all, start the car run until you get multiple errors (probably missing O2 heater error) then plug them back in and clear the codes.

See if the numbers will come back into normal range (0.1 to 0.9v).

If you get values outside of normal you probably need to replace the sensor (use OE or OEM don't cheap out: I need to replace my knock off sensors)
I should have said I recently replaced all of my O2 sensors using Bosch replacements.
Reply With Quote
  #4  
Old 04-02-2019, 10:25 PM
andrewwynn's Avatar
Member
 
Join Date: Jun 2015
Location: Racine, WI
Posts: 10,818
andrewwynn will become famous soon enough
So if you are getting out of possible range it's either a bad sensor or problem in the ECU. The easy test is swapping the two pre cat sensors and resetting adaptations (or as described above recalibrate the DME)
__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)
Reply With Quote
  #5  
Old 04-02-2019, 10:30 PM
Member
 
Join Date: Jul 2016
Location: Menlo Park, CA
Posts: 2,311
Fifty150hs is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
So if you are getting out of possible range it's either a bad sensor or problem in the ECU. The easy test is swapping the two pre cat sensors and resetting adaptations (or as described above recalibrate the DME)
I just tried recalibrating the DME and resetting adaptations. No change.
Reply With Quote
  #6  
Old 04-02-2019, 10:31 PM
Member
 
Join Date: Jul 2016
Location: Menlo Park, CA
Posts: 2,311
Fifty150hs is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
So if you are getting out of possible range it's either a bad sensor or problem in the ECU. The easy test is swapping the two pre cat sensors and resetting adaptations (or as described above recalibrate the DME)
I'll try swapping the sensors this weekend if the weather cooperates.
Reply With Quote
  #7  
Old 04-02-2019, 10:31 PM
andrewwynn's Avatar
Member
 
Join Date: Jun 2015
Location: Racine, WI
Posts: 10,818
andrewwynn will become famous soon enough
Swap the pre cat sensors and see if the problem migrates. It feels like a bad new sensor to me.
__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)
Reply With Quote
  #8  
Old 04-02-2019, 10:39 PM
Member
 
Join Date: Jul 2016
Location: Menlo Park, CA
Posts: 2,311
Fifty150hs is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
Swap the pre cat sensors and see if the problem migrates. It feels like a bad new sensor to me.
I'll try it. I hope that's all it is. FCP will replace it for free!
Reply With Quote
  #9  
Old 04-02-2019, 10:56 PM
upallnight's Avatar
Member
 
Join Date: Aug 2012
Location: Cook County
Posts: 7,280
upallnight is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
O2 can't range to negative values. The precat if reading negative values something is wrong. Looks like a case of problem sensor.

Also: post cat should gravitate to 0.45V so the 0.75 is very high but that can vary a lot.

What I would do: reset all the sensors by unplug them all, start the car run until you get multiple errors (probably missing O2 heater error) then plug them back in and clear the codes.

See if the numbers will come back into normal range (0.1 to 0.9v).

If you get values outside of normal you probably need to replace the sensor (use OE or OEM don't cheap out: I need to replace my knock off sensors)
Actually, for Short term fuel trim or long term fuel trim the value can be negative or positive. Negative STFT will mean that the DME is taking away fuel and positive STFT will mean the DME is adding fuel to the mixture.

The post cat 02 voltage should be at a constant value whereas the pre cat 02 sensor the voltage will vary.

Here's a video on 02 sensors as it relates to voltage

https://www.youtube.com/watch?v=zyh_4SktmFM
__________________
2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
Lotus Europa 1970 S2 Renault Powered
Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
Triumph Spitfire 1971 Sold
Triumph Spitfire 1968 Sold
Plymouth "Cuda" 340 Six pack SOLD
Reply With Quote
  #10  
Old 04-02-2019, 10:59 PM
upallnight's Avatar
Member
 
Join Date: Aug 2012
Location: Cook County
Posts: 7,280
upallnight is on a distinguished road
Here's a video on STFT vs LTFT. You can see that the STFT is negative because the LTFT is positive and the DME is trying to zero out the fuel trim.

https://www.youtube.com/watch?v=WMSM7WAbBss
__________________
2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
Lotus Europa 1970 S2 Renault Powered
Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
Triumph Spitfire 1971 Sold
Triumph Spitfire 1968 Sold
Plymouth "Cuda" 340 Six pack SOLD
Reply With Quote
Reply

Bookmarks

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
Trackbacks are On
Pingbacks are On
Refbacks are On





All times are GMT -4. The time now is 09:20 AM.
vBulletin, Copyright 2024, Jelsoft Enterprises Ltd. SEO by vBSEO 3.6.0
© 2017 Xoutpost.com. All rights reserved. Xoutpost.com is a private enthusiast site not associated with BMW AG.
The BMW name, marks, M stripe logo, and Roundel logo as well as X3, X5 and X6 designations used in the pages of this Web Site are the property of BMW AG.
This web site is not sponsored or affiliated in any way with BMW AG or any of its subsidiaries.