I must be making this problem way more complex than it is and sometimes a fresh mind is what a problem needs. If you have any ideas or thoughts, i'd like to hear it.

car: 1992 Honda Civic
symptom: pin D17 has 4.7v coming out of the ecu with key in on position - wire cut at ecu, voltmeter on ecu side of pin D17. D19 have 5.0v like it should. D21 has the same ground as a23.

done:

grounds are fine and checked.
replaced engine harness.
replaced dash harness (plugs into ecu)
replaced underhood fusebox
replaced underdash fusebox
replaced main relay

main relay 12v powering injectors, iacv, ecu 12v all fine
a23 ground is fine