83 280ZXT, spark but not able to break ground

TimZ — Sun, 17 May 2026 00:55:48 GMT

I picked up a 1983 Datsun 280zx a few years ago. Couldn't get spark and just let it sit. Finally have time to mess with it and haven't had any luck. I'm ignoring fuel issues where tank was still full of fuel from before me (likely 15-20 years old at this point). Going to need a new fuel tank, sender, pump, lines, whatever. Not important to me currently.

I replaced the coil, but the original coil that came with it still functions fine. I have power at Black w/ White Stripe wire next to coil. The yellow wire in that bundle has 12v with key on, blue wire seems to be nothing. I believe the Power transistor is busted, which would have a blue wire coming out of it with a bullet connector. This wire is missing. ECU has a green light that comes on with key on, turns off when cranking, and quickly comes back when cranking stops. I hear clicking whenever the distributor spins to the next firing position. I currently have a PRW-2 in place, middle pin connected to ground, one pin connected to yellow wire, one pin connected to coil negative(per that one PRW2 image floating around). I did swap yellow and coil negative on PRW-2 just in case I got it backward. If I tap yellow wire with jumper, I get spark.
I hooked a digital oscilloscope to yellow wire and saw high pull with key on, low pull with key off, but the pull didn't appear to change when spinning distributor. I don't know how to read an oscilloscope, but I was able to zoom in on the wave and it just looked like noise really.
Here is a rough drawing of current wiring.

If I break the signal wire manually, I get great spark. It just seems the ECU isn't tell it to ground the signal, allowing the coil to respark. I did remove the ECU and opened it up, did not see any burn marks or anything to indicate it should be bad. I tried the GM HEI module in place of the PRW2, but it didn't seem to do anything at all, less than the PRW2.

I have recorded a 3 minute video showing what I have going on, I talk a lot but I think you should be able to follow it.

My current goal is to hear it run. I had a look at the FSM books, but the troubleshooting doesn't really go into detail on what to do if the ECU isn't breaking the signal. What are my likely suspects here? ECU? Where could I locate a replacement? To a point, this vehicle has to pass a state salvage inspection to drive on the road again, so any major overhauls/deletions might be a problem. Located in Ohio.
Looked at following threads(and many others in other sites before posting)

Spoiler

I appreciate any input on what may be wrong here, even if I did something wrong. Thanks.

Edit: 1983 Datsun 280zx w/ Turbo, A/T, 90k miles, USDM. Looks completely stock in the engine bay.

280zx ignition issues

SmoothLight — Wed, 06 May 2026 04:35:59 GMT

Does anyone know of any good videos or guides on installing a switch board and new relay/fuse box on the 280zx? I have a short somewhere that keeps blowing the ignition fusable link. Ive looked everywhere and I have no clue what the issue is. Finally today I plugged in the battery and got magic smoke from every orifice between the fusabe links and the key on. Specifically the white black wire. Could it simply be a bad key cylinder and I dont need to rewrite everything? I feel like it might be better. Any help is greatly appreciated. (Has ms3 pro mini. Was driving without magic smoke before I changed my intake to protunerz)

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83 280ZXT, spark but not able to break ground

280zx ignition issues