Has the loom been messed about with ?
I have seen it once, where a numpty when taping up a loom mixed up the no2 injector connector with the iscv connector, and these were transposed, as they are exactly the same length from inside the loom insulation.
Net result was fuel actually pissing out of the join between turbo and trousers, and running on three, easy fix after I found it.
I thought naturally this was a ecu fault, but the penny dropped when asking owner.
No names though!!
tabetha