1991 ka24de-T25 whats wrong?

[240sxvaj]

i was on my way to get the car dyno tune and i discovered a big problem. the car started boggin as if it was boost leak and then the car starts to idle really low and ends up dying. Been running this car for weeks untuned and not pushing pass 3.5krpm with no problem. until i started leaving for dyno tune and all of a sudden this happened. after letting it cool off i check my boost gauge and drove it without any problem and it ran fine as if nothing happen ANd until i ran it for a couple min then the same thing happened again. boggs at certain rpm and then it dies. i used the scanner on it and it threw out code 45( Injector fuel leak) and EGR which is normal.

i checked for boost leak and i cant seem to find any leaks. also checked for vacuum leaks and the vac gauge reads 19-20. weird because the car idles fine after it cools down and boost fine.
oh yea almost forgot whenever its about to die i gas the car my rpm wouldnt go up.
it will just drop down until i let off the gas and then it idles (back to normal) ok when im not in gear

what can it be?

91 KA24De-srT25(redtop)
running 270cc injectors. have 450cc not installed(d-werks)
stock MAF
walbro 255lph
z32 fuel filter
AFC neo (not installed)
greddy type-M FMIC
HKS hotpipe ssqv combo
phase2 nobrand turbo mani
blitz3'' d/p
megan elbow
delete cat w/buddyclub spec2 exhaust
thanks!