There is no option to have no fuel in the fuel rail if your pump is running (in the right direction) and the tank has some petrol left.
- Check if your hardlines below the car are not bent by skilled workshop technician placing the jack under those.
- Do yourself a favour and assemble two wires with spade/crocodile connectors - allowing you to switch the pump straight to the battery (pump will be running all the time for the time of experiment). Pin up to the tank connectors as your pump is inbuilt.
- Check if you have fuel in the tank (silly but possible if your sender is jammed)
If hard-wired pump will make your engine up and running - the problem lays somewhere between the CPS and ECU or ECU itself. From there you can check every relay on the way and ignition barrel itself…
Priming is automatic (on power-up - the sound of your pump for few seconds), then - depends on ECU.
You haven’t answered if you have alarm/immo installed…
If there is no difference with hard-wired fuel pump - you have internal blockage in the system - imundo the fuel line to the fuel rail and place it in the bucket. Then turn the ignition to confirm it (no fuel running = blockage)