connectors shows 12v. There is a mod that that can be done which turns off the injector 12v when key is Off. Some folks installed this mod (like me) because there's a proven relationship that old style injectors fail prematurely when voltage is applied 24x7 ( the way Nissan designed the early yr cars).
Not sure if your car has this mod from a previous owner? So also check for 12v with cars key turned on.