Seems to be common question, but I havn't seen the answer her. Pleas help before all my hair is pulled.

88 s-10 blazer w/ 2.8l TBI starts w/ fuel sprayed in tb but wont start on own.

tried-new fuel pump,gas tank,pressure regulator,and sending unit (good pressure at tbi now)

also tried different ecm with no change. also tried different fuel pump relay and map sensor. injectors fire well when it starts, so they are not the problem and I have checked and I get voltage at the injectors when I turn on the key.

Out of ideas. Can a week ignition module cause fuel problems?