i have an evo 6 with a few problems, it will boost cut/ fuel cut (feels like hitting a wall) at around 10-12psi it will boost fine untill it hits that boost so i can half throttle it too red line holding the boost at 9psi and it will boos fine. Some other problems that could be the cause are as follows:

Misfires sometimes on idle and de acceleration

Fuel pressure wont go above 40psi when vacuum hose is off on idle

Low running temp/ high rpm idle

If you do a 1st gear pull then put the clutch in the revs will drop and it will stall

Harder to start on cold start, starts fine when warm

Vacuum reads -17/18ish when cold and -20/22 when warm

mod list is:
evo 7 block

evo 6 head

evo 8 turbo

evo 8 injectors

Autobahn88 front mount with stock piping

fenix radiator

550hp walbro fuel pump (unconfirmed only been told from last owner)

38mm wastegate unplumbed

aftermarket dump pipe

steamtube extractors

alloy intake pipe to turbo with big pod filter, still using afm

3 1/2inch turbo back exhaust

turbosmart type 2 bov

Exedy hd clutch

gfb geforce 2 with 3 port mac solenoid

Tomei fpr type s

Things i have changed are:

the tomi fpr - didnt change anything other than stopping it from running rich

New fuel filter

new spark plugs 0.30 gap

replcaed all vacuum lines and silicon joiners on the intercooler piping that had visible damage

has had fresh oil and filter

i dont know what else to look at, next thing im going to change is the fuel pump and the coils too see if they are the problem

also i think it might be the coolant temp sensor on why its running cold?

when i first turn it on it slowly drops idle as it warms up and sits at about 800-900 rpm when the temp gauge reaches about 2 or 3 lines under half way (where it stays) then after a drive it will start idling at around 1.3-1.5k rpm

oh yep sweet, would you know why it runs cold also? Temp gauge goes up to about 2 or 3 lines before the halfway point? And it will slowly go up to halfway line if im sitting in traffic for a long time as in like 20 minutes of just sitting there idling

i have tested the thermo in boiling water and it opens/closes fine, have also put new coolant in and bleed the system

i have been told it should handle 17psi but yeah what do you think i should gap them too?

i did have a gfb geforce 2 with a mac solenoid but im just running wastegate pressure (vacuum line from turbo to bottom port on wastegate) and the wastegate has a 14.5psi spring in it. Yeah i have just gapped the plugs too 0.24 and it seems to help but im gonna try new coils and have a look at the pump aswell

i put a gopro in the engine bay and recorded doing some pulls, if you skip to 1:30 on the youtube video you can see the fuel pressure drop as im still in boost. Will this be a
bad fuel pump? Have tested voltage to the pump and its 12v while cranking the engine, no volts going to it while the key is in the on position tho

i have hardwired the fuel pump and it has fixed the issue now so must of been the wiring to fuel pump/ a bad relay somehwere