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x3 dodgy genuine knock sensors. I'm an engineer by trade and had all the testing equipment I wish I didn't over look the easiest problems first! .. I hope. Either that, or its been a wonderful coincidence that it's started every time since I fitted a new coil, decent NGK one this time. In my removal of components I also reminded myself that about 1/4 of the wires going into the ecu from the loom had been spliced into a piggyback when I got the car and I had hurriedly twisted and wrapped them to get me home...and that was over 3 years ago...and it's been on some seriously long tours in that time 
.. However, I'm still plagued by a bizarre cutting out and hesitation under light load on a long journey. I got hold of a TOYOBD1 diagnostic unit in an effort to monitor a few parameters, however all I'm really seeing is the result of the hesitation/fuel cut on the timing/mixture/inj duration, rather than the cause. Nothing else is going to make an engine stop dead in its track when its fully up to temperature like fuel being suddenly taken away.
(in my case 1.15bar) and around 6000ish rpm, I'm getting a calculated MPG of 1.64... ACE! So when maximum fueling is required the resistor pack is switched out of circuit by the fuel pump relay. The fuel pump relay never actually switches the pump off, just selects the full 12+ volts for high flow or I believe around 8v for lower flow rate."normal" driving. The rest position for the relay is via the coil pack, so I wonder if the relay isn't switching. It looks like pin 6 on the ECU goes to ground to switch the relay via in 1 on the relay, which then takes the coil pack out of use. In the end I took it to my mates garage and we found the ECU was switching the injectors off for no apparent reason. The ECU all looked clean inside, but when I replaced it bingo, no further issues. These sort of issues are always the hardest to track down...(properly this time) and she's been fine for the past few weeks 
I have a few theories regarding the electrical reasoning for this happening, but will save them for a build thread update later in the year. Even though ECU refresh rate is only 1.3s this was still quick enough to show the injector duty returning to idle, along with the IACV, when the TPS was at or around full 90 degrees and boost pressure was X kpa (I can't remember off the top of my head, but around 180 I think at the exact moment before idle conditions). I should also point out that I'm not running crazy boost, you would need to subtract 1 atmosphere from the kpa displayed to show the actual pressurised air charge...or something along those lines.