1987 Chevy Blazer fuel

I would first take a multi meter or a test light and check and make sure you are getting power to the fuel pump. By testing the pigtail to the pump.

If you are not getting power to the pump, then its an electrcal issue, possibly need a new pigtail, fuse, ect.

Also make sure your fuel filter isnt completely clogged up as well.

If it is getting power to the pump, I would check the main line going to the back of the tbi, and see if its getting fuel to that point, your going to need a bucket to catch the fuel if it is.
If its not I would suspect you might have recieved a bad pump.
If you are getting fuel, on the side of the TBI should be a sensor called a TPS sensor or an idle air control, in my 91 s10 it was a four pin hookup, and had alittle spring with a cone shaped tip which would expand or contract to allow or to choke fuel from dropping through the injectors.
I would replace that and see if it starts dropping fuel.

Keep in mind if you drop or splash any fuel in the engine compartment it is very important that you clean and dry it out before attempting to start the vehicle