???bad ecu, cas??

[dr.klawn]

did a S13 Blacktop SR swap for a friend. fired it up & no fuel to #3 cylinder. check continuity to pin #103(#3 inj driver) and all is good. unclipped the other inj's & plugged into #3 & the injector fires. so i have another E5 ECU plugged in & it's still not firing #3!!! any thoughts?

[cotbu]

Does the injector(s) have 12volts key on engine off(KOEO)? I could walk you through a driver test (replacement), but you have almost confirmed it's not the ecu. back probe the injectors and verify 12v continuity to all injector. they should all have the same 12v source.
Anyway if you confirm no 12v repair or (test). make a break out a jumper wire from a 12v source to the faulty injector, spin the cas with your fingers and listen or watch the injector fire.