the sc400 runs the PWM fuel pump ecu and as far as I know the LS400 is two stage resistive.
so with the ls400 ecu and engine wiring - the sc400 fuel pump will always be running in low speed mode - the cold start injector is probably masking the lean out condition until the engine warms up
Well, they can pretty much kiss goodbye to any income from car company hot weather testing now. Our local manufacturers are going to be upset as they use the NT for testing vehicles exported to the Middle East.
Thanks again Gents, I'm over the moon that it has finally been resolved.
The ECU and loom are both off the UZS141 crown and have the same ecu pinouts as the soarer/sc400 just the neutral switch wire colours are reversed. SO after fixing that I now also have the transmission modulating shift...