If the Noid Light did not illuminatethen we know you have no power going to injectors 3 and 4.
Since you have power at injectors 1 and 2 we know you do not have an ASD issue, you have a wiring issue to injectors 3 and 4.
That wiring issue could be anywhere from the injector harness to the PM, you are going to have to check the circuit starting at the injector harness.
Start by testing power at the injector harness connector. (Circuit Z1)
1)If you have power at the injector harness connector (both sides) then you know your issue is in the injector harness.
2)If you have power going into the connector but not coming out the issue is with the connector terminals.
3)If you have no power into the injector harness connector then you have to check the circuit from the PM 10 Pin Connector Cavity #6 to the Injector Harness Connector.
If you have no continuity as listed above that means the wire is broken somewhere in the harness (probably at a splice) and it will require opening the harness to find it or just tapping into the ASD output wire and running new wires to the injector harness connector.
You have a couple of options to do this...
1)Check each section of the harness with an ohmmeter for continuity.
2)Manually actuate the ASD relay and check for power at the injector harness for injectors 3 and 4.
It does not matter where your ASD is located, either in the PM (85-87) or externally mounted (88 - up), you manually actuate it the same way up to 1990.
1)Locate the Diagnostic Connector
(I think it is on the R/S (passenger) on an 85)
2)Using a jumper wire ground the DB/YL wire in the diagnostic connector.
3)Turn the key to the "on" position.
4)The ASD will be actuated, the fuel pump will run and power will be present at the + coil and the fuel injectors on the DG/BK wires.