Engine won't turn over - 1990 300 NT

[JSQ's Z]

I was trying to figure out why my z32 was idling so rough, as if a cylinder wasn't firing. New spark plugs (the ones recommended by Nissan) were installed. No change. I removed one coil pack at a time to see which cylinder may be suspect. Removing all coil packs resulted in rougher idle, EXCEPT when I removed coil pack #2. Thinking I was onto something, I concentrated on that cylinder. Upon closer inspection, I noticed that the fuel injection wires and connectors were badly cracked and corroded. I bought some new connectors and attempted to swap out the old connector with the new one. I did so and started the car. It ran smoother than I had ever seen it run, then all of a sudden, white smoke from under the hood. I had partially melted the #2 coilpack. In reviewing my wiring, I had crossed two wires. No worries. I bought a new coil pack and installed it. Now I cannot get the car to turn over. It just chugs, smells like gas, but never sounds like it wants to start. It is getting spark and plenty of fuel. I've swapped out the PTU (series II) with a PTU from a well running 94 Z32. Still no start. Swapped out the CAS with a known good CAS, still no start. Thinking the worst, I found another ECU (same numbers and letters as the one in the problem Z32) and STILL no start. I have the FSM, but I'm not really seeing anything else to try. I would appreciate any input or suggestions as to what the next item or items I should check. Thank you for taking the time to read this.

[dexter72]

I would remove the #2 spark plug to see if it is wet. If so i would then check the rest of the spark plugs for being wet. I would also remove the connector from the #2 fuel injector, it may be stuck open. Keep that fuel injector disconnected.

 

If the plugs are all wet, clean them with can of brake cleaner spray or a can carb cleaner in a spay can. Then crank the engine over a few times with no spark plugs in it. That will blow out any remaining fuel in the cylinders. Re-install all the spark plugs and hold the gas pedal down to the floor while trying to start the engine. If the engine starts and runs let it clear up then shut it off and re-start it by just cranking it over.

 

I would then connect the #2 fuel injector after the engine is running and see how the engine runs. I am suspecting that fuel injector is bad.

 

You also mentioned that the #2 coil melted, Did you change the wiring to both the coil and the fuel injector?.