Hello all,
After disassembling and repairing 2 burnt wires in the engine fuse/relay block wire harness and replacing fuel injectors, my 1991 LS400 is no longer sparking, or running whatsoever. The wires repaired were Black with orange signal wire to the engine main relay (B9 (2B)), as well as its ground (A5 (2A)). I tested spark with a timing light while the engine is attempting to start, and it does not flash, and it will not run on starter fluid. I have measured voltage to the coils and ignitors from the Black with orange wire and am getting 12V with ignition on. I also tested the connection between the coils and the ignitors via the White with blue, and white with red wires. All relays seem to be turning on normally, and no fuses have blown. The ecu is receiving 12V on IGSW, and outputting 12V through MREL with ign on. The ignition main relay is turning on with ign on, and the COR is turning on when starting.
Hoping someone can give me some insight to what could be stopping the car from sparking, or something that i may have forgot to plug back in.

BACKGROUND:
I purchased the car ($500) in a rough state, running and driving but dumping a large amount of fuel and running very rough. lots of gas in oil and smoke and gas smell in exhaust. Initially I noticed the dome, heater, and ignition fuse had 40A fuses installed, big red flag, so i immediately put the correct fuses in those spots. Firstly i replaced the plugs, dizzy caps, and wires. tested the car and it still ran the same. After that i recapped the ECU (following Yamae's guide) and tested the car with still no change in the way it ran. Finally i tested the fuel injectors and found 2 of the fuel injectors resistance was very high (like 20k ohm), so i replaced all the injectors. at the same time i discovered the aforementioned burnt wires, and decided to replace them at the same time. Now the car no longer starts.

 

UPDATE FIXED
After staring at the wiring diagram for another hour, I decided to test all pins on the ECU. Found that I was not getting 12V at +B or +B1 on the ECU, and tested the B terminal on the diagnostic connector and got 0V. After further investigation i found that the EFI relay was faulty. Although the relay was triggering, some internal short was preventing it from properly switching the circuit which supplied power to the ECU and fuel pump. Replaced with new EFI relay and car started.
On another note the rough running condition was solved by replacing the fuel injectors.

 

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