[Steve Sas]

Make sure you gaped the spark plugs correctly.
There's also the Vanos check filters on the side of the block.
But you usually get related codes if they are blocked.
Are you seeing miss fires when accelerating or are you referring to rough idling?

[Soden82]

Originally Posted by Steve Sas

Make sure you gaped the spark plugs correctly.
There's also the Vanos check filters on the side of the block.
But you usually get related codes if they are blocked.
Are you seeing miss fires when accelerating or are you referring to rough idling?

Just rough idle, specifically cold starts (sitting 8+ hours). Plugs are brand new as of last week and gapped properly using a capping tool to 0.022". These are my second set of plugs since I had my first ones covered in oil from a leaking VC before so I was being proactive.

Cleaned vanos solenoids last week with no change but I don't have vanos codes anyways

[iqraceworks]

From everything you are describing, it sure sounds like a leaking injector. After the car sits all night, pull all of the spark plugs out and see if any of them are wet, or smell like fuel. Even though they new, you could have a bad injector.

If the problem only happens after it's been sitting 8+ hours.....that sure points to a leaky injector. I would check the plugs.....

[Steve Sas]

Cold start rough idling is a tough one. You may need to take car to a mechanic that really knows these engines.
I can list many things that it could be but I might put you off track.
My car was hiccuping on cold start for a while and then just fixed itself somehow??

I suppose you have searched this forum? I'm sure many people have come across this issue.

[iqraceworks]

It's easy to find a leaky injector.....you don't need to pay a mechanic. Just pull the spark plugs after it's sat all night........

If you don't like working on, troubleshooting, and repairing cars...... something with an N54 in it probably isn't the best choice 😀

[Soden82]

Originally Posted by iqraceworks

It's easy to find a leaky injector.....you don't need to pay a mechanic. Just pull the spark plugs after it's sat all night........

If you don't like working on, troubleshooting, and repairing cars...... something with an N54 in it probably isn't the best choice 😀

Been working on it every weekend for the past few months trying new things. Gonna pull plugs this weekend again

[chiefsotos]

Check this out: https://www.e90post.com/forums/showthread.php?t=1726546
Problem solved with hpfp

[Saif2018]

Originally Posted by Soden82

Cold start misfires even on stock map. Gonna pull plugs again to check for injector leakage.

Can't imagine that all 3 new injectors on bank 2 from fcp euro could be defective but you never know.

In terms of my original posting, getting a new Bucketed stage 2 pump soon as I don't have E where I live.

Which Index Injectors are you running on all the cylinders?

As mentioned by others you need to get the injectors checked.

[Soden82]

Originally Posted by Saif2018

Which Index Injectors are you running on all the cylinders?

As mentioned by others you need to get the injectors checked.

New index 12 put in a few weeks ago from fcp euro

[Soden82]

Originally Posted by chiefsotos

Check this out: https://www.e90post.com/forums/showthread.php?t=1726546
Problem solved with hpfp

I saw that, my rail pressure is staying very solid throughout pulls, never dipping below 2000psi. No long cranks either. ATM I'm thinking it's one of the pumps or sensors to the pumps

[Saif2018]

Originally Posted by Soden82

New index 12 put in a few weeks ago from fcp euro

Index 12 in all 6 cylinders?

[Emilime75]

Originally Posted by Saif2018

Index 12 in all 6 cylinders?

Good question. Think OP said he replaced 3. Are they all in the same bank? Did you register/code them? What index are the other 3?

[iqraceworks]

Originally Posted by Emilime75

Good question. Think OP said he replaced 3. Are they all in the same bank? Did you register/code them? What index are the other 3?

You don't need the same index injectors in each bank. I have two index 7's and a 12 in the same bank....no issues at all, as long as you code them in with the proper flow rates.

[Soden82]

Originally Posted by Saif2018

Index 12 in all 6 cylinders?

Yes sorry all 6. I apologize for being vague

[Saif2018]

Originally Posted by Soden82

Yes sorry all 6. I apologize for being vague

Did you check all of them?

[Soden82]

Originally Posted by Saif2018

Did you check all of them?

I did not pull them to see if they're leaking. On a recent cold start log my AFR on bank 2 and STFT on bank 2 is showing lean, so going to check for vacuum issues now.