You will have to find out if you have spark on the cylinders that aren't firing and go from there

 

all cylinders are getting spark, i found that 2,3,5 and 8 injectors aren't spraying. so has something to do with wiring, could the pcm cause only 4 injectors to work? is it possible that i have the wrong harness, im using a stock truck harness, i went over the wires i repinned for dbw swap but they were correct

 

so every injector has a constant 12v at the injector? The PCM will give a ground to the injector .

 

i haven't checked for 12v, ill check that out next. ill check back in after i test that, thanks

 

sorry it took this long to respond but i checked for 12v and they all seem to be getting 12v. i hooked up the noid like and this i what i found( video down below). on my #2 cylinder it flashed for about 5 seconds and then nothing after that

 

my ecm was the problem switched it out and now shes running on all 8, but did notice its would idle real low after a hard rev