Not sure. But I know your having a lot of trouble, to the point anything's almost worth trying by the sounds of it.. but have you tried swapping the ecu for a 1.3 one, just in the slight of chance that could be the problem, just thought I'd mention something pal. Hope you find a fix.
If you want to test ECU I have a non nats one laying around also if you need a tb I have one of those aswell