Serious STFT and AFR issues

Devildog0905 · 11-02-2019, 05:58 PM

I am attaching a link to my datazap. I uploaded two logs while cruising that show how my STFT and AFR bounce all over the place. This issue is only at cruising. My WOT logs look nice. I have changed the spark plugs with one step colder, index 12 injectors, and both rear oxygen sensors. After reading alot I thought it was the o2 sensors but after changing them (with Bosch OE ones), the problem persists.

Current mods: dps, full custom exhaust, dcis, fmic, chargepipe and BOV, MHD stage 2.

I have not changed My pre turbo O2 sensors. Not sure the age.

My coils are about three years old. Eldors.

Please help. This issue is super annoying.

https://datazap.me/u/devildog0905/st...og=1&data=3-24

relative4 · 11-02-2019, 06:28 PM

The upper O2 sensors, not the lowers, are used to adjust AFRs.

Devildog0905 · 11-03-2019, 07:01 AM

Quote:

Originally Posted by relative4

The upper O2 sensors, not the lowers, are used to adjust AFRs.

Ordering the front o2 sensors today. Any other suggestions or thoughts?

Devildog0905 · 12-07-2019, 02:22 PM

Quote:

Originally Posted by Devildog0905

Ordering the front o2 sensors today. Any other suggestions or thoughts?

Problem is still ongoing. I am including my most recent log showing what is still happening. So far I have changed:

Front and rear o2 sensors with Bosch OE
NGK spark plugs
Index 12 injectors

I don't know what else can be causing this.

https://datazap.me/u/devildog0905/stft-issues-still?log=0&data=18-24

type-dRew · 12-07-2019, 04:19 PM

Quote:

Originally Posted by relative4

The upper O2 sensors, not the lowers, are used to adjust AFRs.

Both are used to determine trims. Primaries are just more important.

KClemente · 12-08-2019, 06:00 PM

Did you try to reset lambda adaptations? Reset both sensor and regulation.

BM3Rrrr · 12-08-2019, 06:31 PM

Quote:

Originally Posted by KClemente

Did you try to reset lambda adaptations? Reset both sensor and regulation.

+1 for adaptation reset, use INPA

Devildog0905 · 12-08-2019, 07:51 PM

Quote:

Originally Posted by BM3Rrrr

+1 for adaptation reset, use INPA

Can I just reset them with MHD?

BM3Rrrr · 12-08-2019, 10:00 PM

Quote:

Originally Posted by Devildog0905

Can I just reset them with MHD?

You can and see if it improves, though the only proper way to reset A/F adaptations is through INPA.

Chris@VargasTurboTech · 12-09-2019, 11:45 AM

There are a few different ways to reset it "properly". Bav Tech tool will do it too.

Devildog0905 · 12-09-2019, 06:07 PM

Quote:

Originally Posted by Chris@VargasTurboTech

There are a few different ways to reset it "properly". Bav Tech tool will do it too.

Unfortunately I don't have the back tech tool. I am going to try to borrow a laptop so I can try inpa (I have a MacBook). I'll see if that works. I have protools and mhd.

RoughKnight · 12-11-2019, 07:50 AM

Would ProTools do it?

Devildog0905 · 01-08-2020, 06:21 PM

Quote:

Originally Posted by RoughKnight

Would ProTools do it?

I tried it in protools and I still have the same issue. STFTs going crazy when cruising and getting the 29E0 and 29E1 codes. I'm not sure what else to do. Any suggestions?

BM3Rrrr · 01-08-2020, 06:32 PM

Post a 3rd gear WOT log, curious to see if the trims are lean under load

zomski101 · 01-08-2020, 07:07 PM

If you are getting mixture codes and since you already reset adaptations, try replacing vacuum lines and/or do a smoke test.

Devildog0905 · 01-12-2020, 10:34 AM

Quote:

Originally Posted by BM3Rrrr

Post a 3rd gear WOT log, curious to see if the trims are lean under load

I will try to post one today.

I will also check the vacuum lines. Not sure how to do a smoke test but I will check all of the lines

Devildog0905 · 01-13-2020, 04:30 PM

Quote:

Originally Posted by BM3Rrrr

Post a 3rd gear WOT log, curious to see if the trims are lean under load

Log showing the STFT and A/F at cruise:

https://datazap.me/u/devildog0905/st...og=0&data=3-24

Small pull:

https://datazap.me/u/devildog0905/sm...og=0&data=3-24

WOT pull (best I can get around here on snow tires):

https://datazap.me/u/devildog0905/wo...og=0&data=3-24

BM3Rrrr · 01-14-2020, 12:34 AM

Your WOT throttle trims don't look too bad but yes you are running a bit lean on both banks. I would keep searching for a vacuum leak of some sort.

Many things can cause 29E0/29E1 mixture codes, could be a sensor/air leaks/injectors

Devildog0905 · 01-15-2020, 03:39 PM

Quote:

Originally Posted by BM3Rrrr

Your WOT throttle trims don't look too bad but yes you are running a bit lean on both banks. I would keep searching for a vacuum leak of some sort.

Many things can cause 29E0/29E1 mixture codes, could be a sensor/air leaks/injectors

I just ordered 20 ft of vacuum line. I'm gonna just replace all of the lines and see what happens

Devildog0905 · 01-21-2020, 03:03 PM

Quote:

Originally Posted by BM3Rrrr

Your WOT throttle trims don't look too bad but yes you are running a bit lean on both banks. I would keep searching for a vacuum leak of some sort.

Many things can cause 29E0/29E1 mixture codes, could be a sensor/air leaks/injectors

I replaced all of the vacuum lines and the issue is exactly the same. Not sure how to do a smoke test. I am wondering if I got a bad set of injectors.

BM3Rrrr · 01-21-2020, 05:23 PM

Quote:

Originally Posted by Devildog0905

I replaced all of the vacuum lines and the issue is exactly the same. Not sure how to do a smoke test. I am wondering if I got a bad set of injectors.

Could be...did you buy them from FCP? if so they have a lifetime warranty so you can return them

Devildog0905 · 02-10-2020, 06:02 PM

Quote:

Originally Posted by BM3Rrrr

Could be...did you buy them from FCP? if so they have a lifetime warranty so you can return them

I did not. I bought them second hand.

Quick update. I installed my dp fix for my emission test. Seems like the problem is almost non existent now. Wierd. Any idea what that could mean?

11-02-2019, 05:58 PM	#1
Devildog0905 Private First Class 13 Rep 189 Posts Drives: 2007 BMW 335i Coupe Join Date: Oct 2016 Location: Farmington, NY iTrader: (1)	Serious STFT and AFR issues I am attaching a link to my datazap. I uploaded two logs while cruising that show how my STFT and AFR bounce all over the place. This issue is only at cruising. My WOT logs look nice. I have changed the spark plugs with one step colder, index 12 injectors, and both rear oxygen sensors. After reading alot I thought it was the o2 sensors but after changing them (with Bosch OE ones), the problem persists. Current mods: dps, full custom exhaust, dcis, fmic, chargepipe and BOV, MHD stage 2. I have not changed My pre turbo O2 sensors. Not sure the age. My coils are about three years old. Eldors. Please help. This issue is super annoying. https://datazap.me/u/devildog0905/st...og=1&data=3-24 __________________ 2007 335i Coupe // DIY Single Turbo kit // JB4 with MHD BEF // Custom Exhaust
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11-02-2019, 06:28 PM	#2
relative4 Major 611 Rep 1,272 Posts Drives: '08 335xi E90 MT stage 1+ Join Date: Feb 2019 Location: Denver, CO iTrader: (0)	The upper O2 sensors, not the lowers, are used to adjust AFRs.
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12-08-2019, 06:00 PM	#6
KClemente Private First Class 105 Rep 183 Posts Drives: E90 335i Join Date: Feb 2018 Location: Illinois iTrader: (0)	Did you try to reset lambda adaptations? Reset both sensor and regulation.
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12-09-2019, 11:45 AM	#10
Chris@VargasTurboTech Lieutenant Colonel 1932 Rep 1,532 Posts Drives: All Things TurboCharged Join Date: May 2016 Location: Bay Area iTrader: (0)	There are a few different ways to reset it "properly". Bav Tech tool will do it too.
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12-11-2019, 07:50 AM	#12
RoughKnight Private First Class 54 Rep 174 Posts Drives: BMW 335xi N54 Auto Join Date: Apr 2019 Location: Ottawa Ontario iTrader: (0)	Would ProTools do it? __________________ -------------------------------------------------------- ARM CP, DP, 7.5 FMIC, TiAl Q Bov MHD Stage2+/xHP/xDelete Road to 500hp daily on the way (ya right lol) --------------------------------------------------------
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01-08-2020, 06:32 PM	#14
BM3Rrrr Davy Jones, Giant Squid 271 Rep 913 Posts Drives: a Pirate Ship Join Date: Jun 2015 Location: The Isle of Tortuga iTrader: (0)	Post a 3rd gear WOT log, curious to see if the trims are lean under load __________________ 2010 e90 335i LCI - xHP - Mishimoto - BMS - CPe - Turbosmart - MHD - Eibach - Koni - VMR - LUX
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01-08-2020, 07:07 PM	#15
zomski101 Private First Class 55 Rep 147 Posts Drives: 2009 BMW 335i Join Date: May 2018 Location: Chicago, IL iTrader: (0)	If you are getting mixture codes and since you already reset adaptations, try replacing vacuum lines and/or do a smoke test. __________________ 09 335i - MMP stage 3, fbo
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01-14-2020, 12:34 AM	#18
BM3Rrrr Davy Jones, Giant Squid 271 Rep 913 Posts Drives: a Pirate Ship Join Date: Jun 2015 Location: The Isle of Tortuga iTrader: (0)	Your WOT throttle trims don't look too bad but yes you are running a bit lean on both banks. I would keep searching for a vacuum leak of some sort. Many things can cause 29E0/29E1 mixture codes, could be a sensor/air leaks/injectors __________________ 2010 e90 335i LCI - xHP - Mishimoto - BMS - CPe - Turbosmart - MHD - Eibach - Koni - VMR - LUX
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