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You can check the situation with a specialized mechanic. I'm sure there're mechanics out there who can fix spark issues, like gjdrivelines.com.au, my mechanic
 

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93 NA ATX 3000gt DOHC
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I just tested all the ECU pins and all of them are spot on
That tells me your MFI is working perfectly and has no problems. To help you understand power side of relay is closing sending power to ECU pins 12 & 25 and it confirms ECU is grounding pin 38 to make it do that.

Also the fuel pump side is closing which is confirmed by readings on pin 8 of ECU, which also confirms ECU is doing its job there and that MFI relay is working also for pump. This makes me wonder why you have to hot wire pump. Maybe you don’t know pump will not start UNTIL starter circuit is energized (key to start position). Once started it will only run for short period and if ECU doesn’t receive engine running signal during that period it will shut pump off.

The other readings just confirm ECU is getting proper power when and where it should be. All this confirms only a few of ECU operations are performing as they should, but better than nothing.

There’s another test to see if you need pump hot wire or not, as it could be flooding engine if connect to long before trying to start if injectors are leaking a little.

TEST: Leave pump jumper off, connect volt meter to pump Black test connector we talked about earlier (it may have plastic cap on it that must be removed to get to wire contact point), turn key to start position cranking engine a little (just enough to know starter engaged) and see if you have ~ 12 volts on meter for short period (at least while cranking). If you do, you don’t need the pump jumper at all.
 
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