Young.gio

So my 93 300zx check engine light came on recently. After this light appeared my car starting having irregular idle and loss of power. I figured it was some sort of misfire. So what I did was disconnect the plug that is connected to the coils while the car was on in order to see if a cylinder wasnt working. Sure enough when I disconnected the middle coil from the passenger side there was no change in the idle suggesting that cylinder is bad. So I swapped spark plugs and then I swapped coils and still the same cylinder doesnt work. Any suggestions on what the problem could be? Im thinking either fuel injector or the wires connecting to the coil are not supply current (I just dont know how to test this or replace the wires).

NismoPick

It's very common for the injectors to die on the Z32. (sad face). If swapping coils didn't change anything, then it's either a dead injector, or bad compression.

Cobalt60

I didn't see where you checked the engine codes to find out what caused the check engine light. That would provide good information before you get too far down the rabbit hole.

There are lots of things that can cause a rough idle and loss of power. Find out what caused the CEL first.