Don't know if there is any difference in a Mondeo.
The pump pressure is controlled by the computer as measured by the fuel pressure sender in a non-return system. The fuel pressure is calculated by load as measured by RPM, throttle position, and air intake.
The big question is what does the pressure do as the engine is started. It should fall by 12 psi or so as the engine fires up if it runs long enough to see. If it does not I would say either the fuel pressure sender is bad or the box driving the pump. If it falls to low as the engine runs, that should mean you have a flow problem. Take the line off and feed it into a can so you can measure and compare to the pump flow rating. What the pressure does after it dies is probably of no concequence.
