Thanks for the reply and the diagram, it's slightly different to what I have though. Mine has a 9 way plug joining the engine loom to the car loom with:
Solid brown wire
Solid white
White with green
White with purple
Black with pink
2solid yellow from same pin
Brown with blue
Yellow with black
Black with grey
On the car side.
So far I think I've worked out
Solid brown wire is constant 12v from battery
Solid white ignition live
White with green
White with purple is fuel pump
Black with pink
2solid yellow from same pin
Brown with blue
Yellow with black Efi warning
Black with grey