ka24de Hard to start

[sccr2114]

I have a ka24de and replaced maf, cap, rotor button, plugs, wires, injectors, fuel filter. This being said a week ago i had rough idle and engine would cut in and out often. Ireplaced maf and nothing i then did all the others listed and nothing so i warranty the maf and this fixed that issue guessing it was bad out of box. I installed a Autometer air/fuel gauge before cranking again. now the car will turn over but never run or even at like its getting fire untill i Give full throttle after this it cranks fine. it have a strang idle almost like a mis sound but doesnt seem to have an auctual mis. After i give gas above 1700 rpm the car runs perfect i have thought about it for days and i draw a blank some one please help. Not sure if the upgrades i have installed could cause i would say no but do not know for sure it has an injen intake, pace setter header into high flow cat into 3'' stainless megan racing cat back.