Fuel Trim Code 3.0i M54

[AR_X5]

Hi, I am getting a code for my fuel trim.
E4- Lambda regulator deviation bank 2.

I had a code last winter saying both fuel trims were running rich based off a generic scanner that I had at the time.

The car misfires a little on cold start but it lasts a fraction of a second. I would misfire (as it sounds to me) for literally half a second then all good but only when cold. The car runs fine just this code that surprised me yesterday. I took apart all of the intake boots and non were cracked. I replaced the one going to the throttle body and ICV a while back and while I was at it I checked the DISA and cleaned both the Throttle body and ICV.

What are your thoughts?