Hi, What Engine is this? The fault code 2A61 is "VVT-Teaching function at stop". This is, I believe, referring to the valvetronic motor(large silver thing just above your red circle) I think the plug you refer to is an ignition coil supply.(edit-probably not) I am not sure I can be of much help but I'm sure others will be. In the meantime here is a link with regard to a BMW E90 unit which covers all of this, hope it provides some answers.
http://www.pelicanparts.com/BMW/techarticles/BMW-3-Series-E90/FUEL-Valvetronic_Motor_Replacing/FUEL-Valvetronic_Motor_Replacing.htm