need help, cant figure this out

Ok, heres my problem i have an 87 blazer with a 350 tbi, and it died on me the other week and it wouldnt start back up, so i change the fuel pump cause i didnt hear it working when the key was turn to the on postition. That didnt work so i moved the next thing, oh and i wasnt getting any fuel to the carb so i change the injectors and the connections for the injectors, i also change the fuel filter, and it still does want to start, i put some gas in the carb and it started for a couple second, im stumped now any help would be great!