Splicing in some new connectors for my primary and secondary injectors and a thought crossed my mind. Couldn't find the answer anywhere else on the forum so here we go.
Car is an S4 NA. These have the standard EV-1 connectors. There's 2 wires that go to the connector (what I assume to be positive and ground). Does it matter which pin on the injector gets powered and which one sees ground? Or is it that as long as the injector is seeing voltage across the pins, it'll fire?

 

you are correct, the black wire is power, and the other one goes to the ecu to be grounded.
the polarity doesn't matter, although you'll see that the harness is setup so every connector is the same, i guess just good tidy work.

 

Understood. Much appreciated!