'89 240sx KA24e fuel injector fuse location?

[parleykoster]

My '89 KA24e is only getting power to the injectors on cylinders 1 and 3 (tested with noid light), and I'm a little bit embarrassed to say that I can't find the fuse(s) for the fuel injectors. Does anyone know where they might be located, or alternatively, why only cyl's 2 and 4 would not be getting power to the injectors?

[VStar650CL]

Main ECM power comes from the same fuse as the injectors, so you clearly don't have an injector fuse problem. The injectors are powered in common from the ignition switch and grounded individually by the ECM to fire, so all four should have power whenever the key is on. If there's no power at just 2-4, it has to be a wiring issue.

[parleykoster]

It would make sense for it to be a wiring issue, except that I just installed a new ECU (MS2 PNP), but before installation I tested and confirmed that all 4 injectors were firing with a noid light using the old ECU. Now I'm trying to figure out if this is an ECU hardware issue or a software issue in Tuner Studios. I'm very new to electronic tuning, so this has been a very slow and painful process.

[VStar650CL]

Then it may not be a power problem at all. Check the connectors, all 4 should have one pin that's hot any time the key is on. If 2 and 4 aren't hot then it's wiring, if they are then the power is there but your ECU isn't tripping them.