I have a sneaking suspicion i may have killed some of the wiring in that area, damn nissan engineers. There are two wires in the ecu loom that are identically marked (black, red trace, silver spot) and the same gauge, sitting right next to each other. One of them is the IGN +12v line for the ecu, the other is some random ground line. So of course first time round, i spliced 12v into the wrong one didn't i?, turned the igntion on to see if i had 12v at the ecu connector (thankfully without the ecu plugged in, and all i got was a very warm, slightly melted ground line : ( I was hoping that it might have just melted the insulation off the wire, and that the core and surrounding wires were ok, but it seems now that i've killed the sender wire. The sender itself seems ok, reads 2.2k, which is better than open or closed i guess. hopefully it's just the wire, and hopefully just that one. But it does mean i have to pull the loom out from the intake manifold, unwrap the whole thing, check the wires and re wrap it all.
Oh well, i guess it might be a good chance to pull the injectors out and see if they're working.