[Beisofmarko]

Hey,

I have -06 e92 335i n54 and i've been trying to troubleshoot my rough idle and
jerkiness when starting to drive from stop.

Last week i had my intake valves walnut blasted hoping that would fix the problem but it didn't.
However the guy who did blasting found out that some of the previous owners had
changed cylinder 3 injector and probably cheaped out in wrong place?

So i currently have following injectors:
- Cylinder 1 = Index 10
- Cylinder 2 = Index 10
- Cylinder 3 = Index 11
- Cylinder 4 = Index 10
- Cylinder 5 = Index 10
- Cylinder 6 = Index 10

From what he told me and what i googled, i should not have index 11 or 12
mixed with index 10 or lower atleast in the same bank?

He said that i should start troubleshooting from this as he didn't expect my HPFP
to be the case as my car is not cutting or jerking on WOT.

So, could this index 11 injector be cause for my problems or what i'm really looking at?
If yes, should i change cylinder 1 and 2 injectors to Index 11 aswell and get them coded
or change all 3 or all 6 to index 12?

edit: forgot to mention, i'm not getting any shadow codes or active codes related to this at all.
So symptoms are just rough idle (rpm's jumping occasionaly between 600 to 700ish), occasional
shakes on seat and sometimes jerking when starting to drive from stop (mostly when engine is cold).
On WOT car pulls great.

Thanks!

[MysticRob]

Depends on who you ask.
The BMW literature does indeed say not to mix older injectors with newer ones, but for the life of me and many others we can't figure out WHY that's recommended. Many of us think it's just so they can sell more injectors. LOL
To my knowledge the DME doesn't look at anything beyond the #s coded into it from each injector, and looks only at each injector's parameters individually, not as a group, so why would an old index in one bank affect newer indexes, and vice versa, in the same bank? To my knowledge, they wouldn't. It just doesn't make sense.

Beyond the injectors, have you pulled the plugs to check them, or thought about installing all-new coils? As for the injectors, don't just trust the replacement having a good seal, or good decoupler. For peace of mind you might think about having all 6 updated to index 12s.

Did BMW start selling the 335i in 2006 in Finland, or was that a typo?

[Beisofmarko]

Originally Posted by MysticRob

Depends on who you ask.
The BMW literature does indeed say not to mix older injectors with newer ones, but for the life of me and many others we can't figure out WHY that's recommended. Many of us think it's just so they can sell more injectors. LOL
To my knowledge the DME doesn't look at anything beyond the #s coded into it from each injector, and looks only at each injector's parameters individually, not as a group, so why would an old index in one bank affect newer indexes, and vice versa, in the same bank? To my knowledge, they wouldn't. It just doesn't make sense.

Beyond the injectors, have you pulled the plugs to check them, or thought about installing all-new coils? As for the injectors, don't just trust the replacement having a good seal, or good decoupler. For peace of mind you might think about having all 6 updated to index 12s.

Did BMW start selling the 335i in 2006 in Finland, or was that a typo?

It was not a typo, my car is indeed 09/2006 and was imported from germany
in 2011 if i recall correctly. I believe 335i has been avaible from 2005 allready, atleast in germany.

I have not pulled the plugs and checked them, will do someday soon.
Didn't think about coils yet as most of threads with similar problems lead to injectors after all.

As for injectors, i don't know the right answer but i found this quote from bmw:

"IMPORTANT:
Injectors with index 11 and higher have a different calibration and construction than injectors with index 10 and lower.
Due to this difference, the injectors with index 11 and higher and injectors with index 10 and lower cannot be mixed
on the same engine bank (i.e., cylinders 1*3 or 4*6)."

and from another topic:

"The DME assumes each injector in a bank operate the same and thus applies the same fuel trims and adaptation values to all 3 injectors on each bank. If one of them is operating differently, it will skew these values and cause all 3 cylinders to run poorly: 1 too lean and 2 too rich, or vice versa."

[MysticRob]

Originally Posted by Beisofmarko

It was not a typo, my car is indeed 09/2006 and was imported from germany
in 2011 if i recall correctly. I believe 335i has been available from 2005 already, at least in germany...
and from another topic:

"The DME assumes each injector in a bank operate the same and thus applies the same fuel trims and adaptation values to all 3 injectors on each bank. If one of them is operating differently, it will skew these values and cause all 3 cylinders to run poorly: 1 too lean and 2 too rich, or vice versa."

I should've asked if it was actually a 2006 model year, not when it was made, since new model years usually come out ~September of the previous year.

As for the DME quote above, it doesn't really make much sense to me either. Why bother to code each injector individually into the DME if the DME "applies the same fuel trims and adaptation values to all 3 injectors on each bank". I may not be understanding that correctly, and I'm not expert on the DME, so maybe someone else will have some more input. And what exactly does "if one of them is operating differently" mean according to BMW? Differently how?

[NoQuarter]

Each bank has only one o2 sensor so each bank is treated as a whole for fuel trims.

Can't adjust a single injector based on a measurement of 3.

They have calibration numbers sure but if they are indeed made differently then they don't behave the same and deliver different quantities of fuel.

I think if they were as accurate as implied then there would be no need for feedback from an o2 sensor.

[feuer]

Originally Posted by MysticRob

I should've asked if it was actually a 2006 model year, not when it was made, since new model years usually come out ~September of the previous year.

That would be in the wonderful USA but not elsewhere In most EU countries title and registration are same document. Car manufactured Dec 5, 2005 sold and registered Dec 25, 2005 would be 2005 car in official documents.

[feuer]

Originally Posted by NoQuarter

Each bank has only one o2 sensor so each bank is treated as a whole for fuel trims.

Can't adjust a single injector based on a measurement of 3.

They have calibration numbers sure but if they are indeed made differently then they don't behave the same and deliver different quantities of fuel.

I think if they were as accurate as implied then there would be no need for feedback from an o2 sensor.

It doesn't really work like that. That is why there is cylinder synchronisation based on feed back from O2 sensor for long term fuel trim and crank possition, knock and cam shaft possition sensor for timing. Often misfire would continue on single cylinder after injector, spark plugs and coil have been replaced. Deleting the adaptations in that case would remedy the issue unless there is internal engine issue. There are plenty of threads about rough idle. What is the most frequent recommendation? Reset adaptations. You have it as feature in JB4 and MHD that delete throttle and lambda only. With INPA you can do knock and cylinder compensation and synchronisation.

[feuer]

Originally Posted by Beisofmarko

So i currently have following injectors:
- Cylinder 1 = Index 10
- Cylinder 2 = Index 10
- Cylinder 3 = Index 11
- Cylinder 4 = Index 10
- Cylinder 5 = Index 10
- Cylinder 6 = Index 10

Since all injectors have been replaced you need to make sure they are properly installed and coded to your car. After that delete the adaptations. The problem might not be with the injectors at all. So I suggest you go a log during those times that you car is acting up, like at idle, after stop and etc. Do you experience loner crank? How are your alternator and battery?

[Beisofmarko]

Originally Posted by feuer

Since all injectors have been replaced you need to make sure they are properly installed and coded to your car. After that delete the adaptations. The problem might not be with the injectors at all. So I suggest you go a log during those times that you car is acting up, like at idle, after stop and etc. Do you experience loner crank? How are your alternator and battery?

Thanks for the reply, i'll try find someone with INPA to check if i have right
values coded. I'll take a log on idle aswell.

I'm not quite sure what loner crank means but car starts normally, i have not
measured alternator, will do.
Battery is less than 6 months old.

[feuer]

Originally Posted by Beisofmarko

Thanks for the reply, i'll try find someone with INPA to check if i have right
values coded. I'll take a log on idle aswell.

I'm not quite sure what loner crank means but car starts normally, i have not
measured alternator, will do.
Battery is less than 6 months old.

Longer crank means does it start right up or cranks a little before it does. Is it smooth while cruising on the hwy at constant speed? Could be a lot of things. Best would be to log to see what is going on.

[Beisofmarko]

Originally Posted by feuer

Longer crank means does it start right up or cranks a little before it does. Is it smooth while cruising on the hwy at constant speed? Could be a lot of things. Best would be to log to see what is going on.

I took few logs with MHD, does something seem wierd here?

Idle with cold engine: https://datazap.me/u/beisofmarko/idl...og=0&data=3-24

Idle with warm engine: https://datazap.me/u/beisofmarko/idl...og=0&data=3-24

Steady highway cruising: https://datazap.me/u/beisofmarko/hig...og=0&data=3-24

3rd gear pull: https://datazap.me/u/beisofmarko/3rd...og=0&data=3-24

Thanks!

[feuer]

Originally Posted by Beisofmarko

I took few logs with MHD, does something seem wierd here?

Idle with cold engine: https://datazap.me/u/beisofmarko/idl...og=0&data=3-24

Idle with warm engine: https://datazap.me/u/beisofmarko/idl...og=0&data=3-24

Steady highway cruising: https://datazap.me/u/beisofmarko/hig...og=0&data=3-24

3rd gear pull: https://datazap.me/u/beisofmarko/3rd...og=0&data=3-24

Thanks!

I'm not an expert and is better to post these in the log help section as we. I see bank 2 running lean sporadically. That is cyl 4-5-6. Is either coil, spark plug, injector or o2 sensor.

[Beisofmarko]

I pulled out old plugs today and replaced them with new oe bosch plugs.
Also changed the position of coils (cyl. 1,2,3 to 4,5,6 and vice versa),
shouldn't this eliminate faulty coils right away unless bank 2 problems move to bank 1?

As for old plugs, there was little wetness on cylinder 2 plug, very watery (fuel?).
I tried to smell it but couldn't tell for sure if it was fuel or not.

Took 2 new logs afterwards if someone can tell if theres any change?
(I'll post logs on mhd datalog section aswell).

3rd gear pull: https://datazap.me/u/beisofmarko/3rd...og=0&data=3-24
Idle, warm: https://datazap.me/u/beisofmarko/idl...og=0&data=3-24

First time i've changed spark plugs so i took few photos, do they look normal
and does that cylinder 2 plug indicate leaking injector?

View post on imgur.com

View post on imgur.com

View post on imgur.com

Thanks!