Re: Brief introduction
Belated thanks for the welcome, folks.
Finally got around to fixing my GTV. Turns out the problem was a fault in the "red stripe" relay, the one in the group of four (at the back of the engine bay) that feeds the ECU. I popped in a standard, new relay and the Code light went out, engine started right up. Glad I didn't give up and spend a fortune getting the thing towed to the workshop. Total repair cost (Sweden): 46kr. Whee!
The special circumstance here, for others in the same boat, is: "Code light on, injector light off". That clues you in that there's something wrong with the ECU; in this case, it wasn't getting power due to the faulty relay.
I'm going to call a proper Alfa repair shop to check whether that relay should be replaced by a special one of some kind - my guess is yes, as I believe the correct relay has a diode - but nice to have localized the problem. And the proper relay shouldn't be more than 200-300kr.
All of my theories regarding the problem, btw, were developed based on reading around in this forum. Fantastic resource, so huge kudos to you all!