That seems straightforward.

Half the time I tell myself I should have just paid you to build my MS, but the other half I realize I wouldn't learn a damn thing from doing that. I'm gonna get this thing done, I'm just fumbling my way through without trying to have my hand held too much. Stay tuned for more help queries in my own threads.

the learning curve can be very steep. tough getting up it, however it pays off being familiar with the ecu. especially if it is something you drive daily.

Oh yes this has been very very steep for me, but I have to start somewhere.

I am looking at this diagram and trying to understand the next step in connecting my MS3x to my Toyota COPs and injector harness:

Attachment 230577
The COPs harness is wired to the ignitor and has two (2) additional wires that are separate from the stock harness and is intended to allow for sequential spark (instead of the OEM wasted spark system).

Attachment 230578
The injector harness has two (2) additional wires that are separate from the stock harness and wired to injectors #2 and #4. As I understand it, these are intended to run sequential injection.

Questions:
[1] Do the extra COPs wires go to pin '1M' (marked SPARK B MS3x-33) or elsewhere?
[2] Do the injector wires go to pin '2V' (marked as INJ A 2&4 with wire Y/B) or elsewhere?

https://trubokitty.com/#/ms3xassembly

Go to the bottom and select diagram for 90-93. Then at the bottom there is a diagram for sequential injection. You need to make sure that INJ A goes to cylinder 1 (should already be that way), INJ B goes to cylinder 3, INJ C goes to cylinder 4 and INJ D goes o cylinder 2. Same order for IGN coils. INJ and IGN C and D are not going to be found on the diagram you showed above, because there's only 2 wires for each on the factory ECU connector. The extra wires you show need to run directly to the MS3x.

why does your COPS harness have injector wiring?

think about that for just a minute please.

Look again: The COPs have 2 extra wires (for spark) and the injector harness has 2 extra wires (for sequential fuel injection). Or, am I reading you wrong?

Thanks!