Do you just unhook the ecu and do positve to pin a1,etc and the ground to chassis? Im trying to determine if my injectors have resistors already as ive read that neptune needs 10ohms or so and my precisions are 2.1ohms.

 

No you wouldn't, because what you would be measuring is the resistance *AFTER the injectors*, which would probably get you some very low resistance readings.

You want to measure the resistance of the injectors on the injectors themselves. unplug injectors, set multimeter to resistance, and poke the ends into the two terminals/pins on the injector

10-ohm injectors are high ohm, saturated injectors
sub 10-ohms injectors are low ohm, peak-hold injectors.
Remove your resistor box, and you can run the 10ohm injectors

(assuming you run a honda ECU before this, and not some aftermarket ECU with peak hold injector drivers)