Why will my 1990 TBI 350 suburban not let fuel out of the injectors?

My suburban died on the side of the road. I unhooked the fuel lines and turned on the switch. I am getting plenty of fuel from the fuel pump.I rebuilt injectors, then changed out the entire Tbi and still get no gas from the injectors. I'm thinking the computer is gone but why and where do i get one? If i pour gas into the top of the Tbi it will start then die.HELP!!!Why will my 1990 TBI 350 suburban not let fuel out of the injectors?Your pick up coil in the distributor is what times the fuel . It is what i would check. It also can stop firring to your plugs.
Why will my 1990 TBI 350 suburban not let fuel out of the injectors?
It is possible that the computer is not triggering the injectors to open to let the fuel out. I would check first to see if you are getting any voltage to the injectors first. There can also be a short between the computer and the injectors or maybe even some bad sensors not letting the computer know when to fire the injectors. If it is your computer there can be many reasons why it would go. A cheap place to get an oem used computer would be a site called U Need A Part, http://www.uneedapart.com. Just make a request on there and you will get responses back with prices from salvage yards that have your computer.