76 D-jetronics problems, Only one injector working Options

[Malpais82e]

I have a 76 914 that's been in my barn for 10 years. Trying to get it running again. I’ve searched this forum and other forums and the internet extensively, and can’t find an answer, or don’t recognize it!
My questions are:
1: Can bad or maladjusted trigger points shut down 3 injectors and allow one to work?
2: If the throttle switch, when throttle is stroked, cycles one injector about 20 times, shouldn’t it make all injectors click? Just one does.
3: Does the throttle switch bypass the Control Unit or at least the computing in the Control Unit?

What I’ve done so far:
Sprayed gasoline into the throttle body. Ignition system and timing work – thing runs and sounds good.
The relay board and sockets needed cleaning, and I got the relays working so the Fuel Pump and control module have power as I’ve read they should. Fuel pump runs a few second when key is turned on. Pressure is about 30 psi.
I’ve also read that moving the throttle (and switch) should, cause the injectors to “click”). Only #4 cylinder injector does anything.
I then re-did the grounds and rang out the wires to all injectors - grounds to ground and power wires to appropriate connections on the Control Unit - all had continuity.
I took the injectors out and sure enough, only #4 sprays gasoline. If I move the #4 wires to another injector, it works, so only #4 connector is getting a signal and at least one other injector will work if it had a signal.
The rest won't even click. I tried a different control unit – same symptoms and only #4 injector doing anything!
I'm thinking of trigger points, but if they are bad/misadjusted, a pair of cylinders would fail instead of three, wouldn't they? And bad trigger points wouldn't keep the throttle switch from cycling all four injectors, would it?
Thanks for any ideas or guidance. I’m about frustrated and out of ideas. Maybe a little a little dynamite………………………….

Gordon