Check rail pressure: Connector toward back of engine on the fuel line. Get a fuel pressure Gage and manual that gives you the fuel pressure your pump needs to put out.
Some Chevy injector systems require 65 to 95 pounds so require only 15 to 35 pounds. depending on the type on your vehicle. You will need to know that.
Then connect the Gage and turn the ignition on and read the fuel pressure.
If too low bypass the fuel filter or filters and check again. If still too low it is your fuel pump.
If you are going to pull the tank and change it yourself be use you get the right fuel pump from the parts house.
Now one other thing sometimes the return line gets kinked especially if you do a lot of off roading, or you run over something that kicks up and hits the return line.
If that has happened then it will peg out the fuel pressure Gage.
That will also happen if you are having a problem between your fuel pressure Gage and injectors or injector.
To tell if it is the injector system disconnect the return line. Caution you will need a gas can to put the end ot the return line in otherwise you will have gas running all over every where.