1991 Ford Fiesta No fuel

I have just purchased this 91 fiesta from a friend who has tried to repair this fuel system problem. The car was running when it stalled & would not re-start. He replaced the fuel pump & fuel filter. Still no fuel to the engine. Checked & confirmed that the crash relay was not tripped, and he also replaced the fuel pump relay. He has checked that there is 12v to the pump. Finally he removed the fuel lines and blew them out with compressed air. Still no fuel. He gave up & sold me the car.

I need some help as apparently these fuel pumps do not run constantly, so you cannot hear it. I have been informed that there may be some sort of electronic control on the engine (sort of regulator or fuel management) that may be the culprit. However, before I sink anymore cash into replacing parts I am hoping that you can provide some ideas of what to check, where to check and how to check any other components that may create this condition and or, effect the fuel system so that there is no fuel. HELP !