Open injector and OBD losing connection

Given my situation, I'm not sure if this should land in OEM tech or Modified. Mods let me know if I'm in the wrong.

2000, 4.0, AW4
(Wiring harness has been modified to run a supercharger)

The other day when I started in the morning the CEL started flashing and the engine ran rough. Code is P0203, injector coil open. The interesting thing is that when I hooked up my USB - ODBII, when the engine is running I keep getting disconnected from the ECU.

So I think it's an intermittent short that is worse when there is vibration from the engine running. But is it ground? Power? Something else? It's only the one injector, and doesn't move when moving injectors around.

USB cables have historically been known to lose connection intermittently. I think you should unplug the connector and the one at the ECU. Ground the injector wire at the injector connector, then check continuity of the wire from the ECU to ground. Shake the wire harness if it shows good continuity, see if there's a certain way you move or twist it that causes it to go open.

if memory serves me right if an injector shorts out it will "crash" the computer and cause it to reboot. not sure if that's happening or if you have a dodgy reader.