the stock ecu ground on an s4 goes thru the harness and onto the rear bolt of the vacuum rack. the s5's have this one and one more by the ecu itself.

I am going to take pictures when I do the full grounding, I'll write up an FAQ with some good pics.



I think I am going to get a grounding block, run a quality ground to the block, then everything else to the block.



I bought a generic kit from one of my suppliers for $20.00, I haven't got it yet, but I will keep you posted.