1987 Ford Escort fuel pump dies

Fuel pump stops running while driving or idling. I checked the fuel pump voltage with a meter at the inertia switch, EEC Relay and fuel pump relay while cranking engine - the volts drop from 12 v to about 9.5 v when I turn the key from ON to START. I tried all new relays and fuel pump and I get the same voltage readings. I checked for continuity between relays and pump connectors. Something is making the voltage drop through the whole fuel pump circuit. I followed the diagnosis steps using the wiring schematics in the service manuals.

Fuel pump stops running while driving or idling. I checked the fuel pump voltage with a meter at the inertia switch, EEC Relay and fuel pump relay while cranking engine - the volts drop from 12 v to about 9.5 v when I turn the key from ON to START. I tried all new relays and fuel pump and I get the same voltage readings. I checked for continuity between relays and pump connectors. Something is making the voltage drop through the whole fuel pump circuit. I followed the diagnosis steps using the wiring schematics in the service manuals.
So let me get this straight, you changed the fuel pump? And it still dies? Cause you can have all the volts and continuity in the world but if it doesn't hold pressure, it's junk. Try doing a fuel pressure test. It should hold pressure indefinitly. If it leaks down, I would be looking at the pump, or the fuel pressure regulator or a fuel line that is corrored through.
Now if the car just dies. Maybe it's a charging issue.