[E91 Hoarder]

Hi folks. Hope you can point me into right direction or give clues.

Got two codes 29E0 (fuel mixture control) and 29CF (misfire cyl 3). Did some research on 29E0 and found this code could mean a number of things. But there is also a misfire code for cylinder 3. Maybe in combination they could mean something specific? Below is the detailed pull by BT tool.

Car is stock with an exception of intercooler. Plugs and coils were recently replaced.

[mawzi]

I had the same problems. They disappeared after changing the injectors.

[E91 Hoarder]

Originally Posted by mawzi

I had the same problems. They disappeared after changing the injectors.

Did you change them all or only some injectors?

[stewbets]

So you're running the stock tune with an intercooler? Are you using any e85? That code points to fuel trims being outside either their maximum or minimum on bank 1. The fact that cylinder 3 is also misfiring does strongly suggest that injector 3 is the culprit. Do you have a way of logging or monitoring to see if your trims are lean or rich? This is where it's nice to have a spare injector to swap in and test. I have a set of cheap, used injectors that I've used in the past to help troubleshoot this type of issue.

[E91 Hoarder]

Originally Posted by stewbets

So you're running the stock tune with an intercooler? Are you using any e85? That code points to fuel trims being outside either their maximum or minimum on bank 1. The fact that cylinder 3 is also misfiring does strongly suggest that injector 3 is the culprit. Do you have a way of logging or monitoring to see if your trims are lean or rich? This is where it's nice to have a spare injector to swap in and test. I have a set of cheap, used injectors that I've used in the past to help troubleshoot this type of issue.

No tune, all original. Pump gas, no e85.

I am not familiar with logging. Can you suggest how to do it? I have BT cable.

Any caveats with swapping injectors? If I get a used one from a part out, does it need to be coded in? Is it okay to swap only one injector or it needs to be done in certain combinations?

[stewbets]

There are all kinds of opinions on injector swapping. According to BMW each bank must be all index 1 - 10 or all 11 - 12 (no mixing a 12 with a 7 in the same bank, etc.), but multiple people have reported no ill effects from mixing forbidden indexes. Replacing one injector at a time isn't a problem. Also, BMW states the injector seal must be replaced each time it is installed. Most everyone tends to agree with this one (though I did not replace my seals). There's also a tool to install and compress the new seals and a slide hammer to remove the injectors, but it's possible to accomplish both tasks without them. The new injector should be coded. I use ProTool for this because it's easy, but it's not cheap. But it's not the end of the world to take a test drive with a new injector before coding it. As far as logging, I'm only familiar with MHD for this. It requires the $85 monitor license, but I think it's totally worth it for how useful it is.