[335_E90]

Ive been having an intermittent misfire but only happens when i boost....a few months ago i had a cyl4 misfire code so i changed my coil but didnt change anything so i changed my injector. That solved the issue for about 3 months but now its happening again everyday. I put brand new plugs, still misfired. I just changed all my coils today and its still doing the same thing. Im running a stock car with mhd stage 1 91oct and dci. Keeps throwing the same codes everytime. My codes are : 29D0 cyl 4 misfire and also 29ED power management, standby current control. Anyone know what it could be??

[MR.BLUECOLLARMAN]

I heard there were a lot of people having issues with mosfets inside the ECU causing these kinds of issues. Not sure if yours has this potential problem but you can look into it.

[Gohan335i7]

Change all injectors... Walnut Blast done recently ?! :O Say yes...

[msjt]

What index injector did you put in?

[335_E90]

As far as i know walnut blast was never done. For the injector i am not sure i gotta check....was ordered off rock auto

[335_E90]

The injector i changed is an airtex/wells 4G2153.....not sure if that helps?

[nukezero]

you can't mix injectors index 12 with 2009 injectors. I'm guessing you have 2009 stock injectors in there ? at the very least, you need to change the entire bank of injectors and also program them with INPA.

[335_E90]

how do i know which index injector i have? why cant you mix index 12 injectors with 2009 injectors whats the difference?

[Red_Bean_Bun]

The index within the same bank should preferably be the same. And 12 is the latest version for these injectors.

[JDuke335i]

Originally Posted by Slammed_dub

how do i know which index injector i have? why cant you mix index 12 injectors with 2009 injectors whats the difference?

The index # is wrote on the injector

[335_E90]

oh ok thanks guys. i am going to try and do a walnut blasting to see if that will change anything. changing all 6 injectors is very pricey

[2008_e92_335xi]

Almost sounds like you put in an injector with a newer index than the other 5, and it may have worked at first but since it (I assume) wasn't coded, it eventually went back to misfiring. In this situation I feel it's best to do at least one bank of 3, if not all 6 of them at once, if possible. As well as make sure they're coded correctly. I agree that replacing all 6 injectors is not cheap. However I just got a deal on them so if you're looking to buy some I can let you know where I got them.

P.S. I just walnut blasted my car w/ 100k miles on it and it was filthy. I have a hard time believing it was ever done before, there was at least 1/8th" buildup in some spots. It definitely helped the car run/idle smoother, however I don't think that build up would cause this type of misfire (not saying it's impossible) If you can do it yourself, it's worth getting the kit from Bavauto.

[jwebb335xi]

Originally Posted by 335_E90

oh ok thanks guys. i am going to try and do a walnut blasting to see if that will change anything. changing all 6 injectors is very pricey

Did you code in the new injector with INPA?? That's necessary so power and fuel values are known to the computer.