HELP! FG turbo engine in drift car doing weird shit

ok so I'm pretty new to this but the car i have is a nissan cefiro drift car running an FG turbo barra with auto pcm now running manual tr6060 box.
The mods are pretty simple to the engine it has oil pump gears valve springs and 1000cc injectors everything else is basically stock and retains all its factory sensors. I got someone to do the loom and flash the pcm to run without the speed sensor and PATS and he says he has this set up in many working cars.

vid says a thousand words https://youtu.be/S4c7M2NdRNw
fairly sure this is the tune file i have currently on Attachment 82643
I cant flash the car or read it just been using hp to compare my tune to others looking for problems


The problem i have is the car will idle fine it will even drive around fine, when i try and rev out a gear over 3k rpm i get this massive back fire i lose all fuel pressure and i lose complete throttle control for a few seconds then everything comes back.
I've mainly just been trying to trouble shoot the problem now without the car moving (as load doesn't seem to be a factor) if i rev really slowly to 2400-2500rpm the car without fail starts crazy hunting up and down every time it hunts i lose voltage from 13/14v to 12 my fuel pressure dips a lil. If i then rev right past the hunting to say 3k 4k rpm quickly is when i get the massive back fire and lose all fuel pressure for like a second. Not sure if coincidental but it always seems to be on the throttle decel as in i can sit there and rev 3k-4k-5000rpm hold it there (it tries to misfire a bit) but its as soon as i let off the peddle is when i get the fuel cut and backfire.

I know what your thinking that this is a voltage problem where the pcm shuts off for a second and comes back but it isnt. I've torn apart all the conversion loom and engine loom looking for faults but everything looks good, ive back probed all the pcm powers and they never lose more than 12v they only drop from 14 whilst the hunting begins, 5v reference don't drop voltage at all checked all earths added earths swapped to another altenator, new map sensor, new cht sensor tried another crank angle sensor started unplugging sensors but everything made the car worse. When i voltage test the pcm wire for fuel pump ill have zero volts then as soon as it hunts i get 12v so the pcm is commanding the pump to shut off. I even hard wired the fuel pump so it was completely free from the pcm (thinking it was a dead pump causing the hunting) no difference still hunts still backfires (pretty sure its killing the injectors as well as the smart charge on the alt and maybe coilpacks)
Ive o scoped throttle body and the APP thinking it has anomalies but they seem ok when i measure voltage from the peddle versus the TB the voltage will rise steadily with the revs of the engine till it starts to hunt then the throttle body voltage goes back to around idle and the peddle voltage keeps rising as if the pcm knows your trying to accelerate but thinks somethings wrong and shuts everything down. Its also like a lose communications with my scan tool as the throttle % will sometimes hit zero my coolant will lose degrees and even my timing will back right off wether its actually losing comms or just seeing what the pcm is doing idk.

I tried taking this to my local tuner but he said i had a major electrical problem and couldnt finish the tune so he did what he could then i proceeded to rip apart the whole car looking for problems, im 99% sure this isnt a wiring problem as ive traced every wire in the pcm and continuity tested ohms tested everything. I don't see why this would be a mechanical problem as although i bought the engine from a wreck nothing was really damaged and everything is matching the engine the only thing different is the gearbox. This kinda only leaves me with something ins't compatible with the pcm.

should mention im not getting many dtc's getting
p0443 evap control
p0141 o2 sensor bank one sensor 2 (not running second o2)
P1000 powertrain
P1549 think cruise control
P1565 sometimes comes on for that stupid intake actuator thing even though FG turbo doesnt have it
U2514 i think is no speed signal but comes up as nothing on the scanner
Also haven't hooked up reverse lights as i dont think i have the pin in the ecu anymore or brake lights

hey mate, hopefully we can finally get this sorted, can only hope its something simple that's been overlooked somehow, you've def done a much more thorough job troubleshooting/testing shit.

I did the loom and tune for him, at first thought maybe was a wiring issue but as far as I can tell I didn't do anything different to all the other fg looms I've done.
at first was running the zf6 tune ive been using as a work around for the no speed sensor lhm, his tuner then changed it to manual, no change, so I then sent up a tune that's running in matts xd which is making something like 450rwkw and runs 10s, still no luck.

this is doing the same thing a mates el was doing which we tried everything to fix over around a month, but turned out to be a pedal setting issue. the settings I used to fix the el is what is in the xd and a few others, no ones had a drama.
i was going to try sending up another ecu with different pedal settings again and the rest a mostly stock tune, just with the zf settings so it wont go into lhm from no vss, plus another ecu with a 5spd auto strategy which is what i used before we figured out the settings needed for the zf tune to be happy.

they are a different osid so i guess pedal settings is still pretty possible but i think we've tried 3 different sets of pedal data.

at this point even if we can get any change from its current state, it'd help with what to do next.

just spent ages going through heaps of tunes, looks like it's a pedal setting/os mismatch. didn't realise it was the same strategy at first in my mates el, we eventually just tried a different ecu & strategy. i'd sent franky the loom n ecu before all the dramas with my mates car, has been almost a year since so just didn't make the connection.