Hello and thank you for using Just Answer
did you Ohm out the injectors?
they should all be 8-12 ohms or they could be shorting out the injector driver circuit when you plug them in
let me know if you have checked resistance of the injectors
actually they should be 12 or higher I had looked up the spec for a cutlas ciera
but if they are over 10 that is probably not the cause of the injector driver circuit shorting out.
sounds like the load of the injectors could be shorting out the driver in the ECM
I would double check the harness back to ECM if the harness checks out its probably a short in the computer
click here for a diagram of your engine control circuit
the pink runs to the injector fuse
the dark blue runs to two seperate pins of the ECM
I would unplug the ECM and all injectors
then check for continuity between any of the pins and ground... if you have continuity then you have a short to ground
if there is no short to ground it sounds like the ECM is shorting
there is nothing else in the circuit