FP testing calls for more than running pressure.
The first reading is at idle
You are looking for 3.2-3.6 bar -This test both the pressure to injectors and the regulator for specs...
Next test is to disconnect the vac line to the regulator [ in front of the test port]
The pressure should now increase to 3. 7-4.2 [unregulated pressure / actual pump pressure].
Next test is to turn key OFF for 30 min and see if pressure HOLDS ...spec on your car for this test is no less than 2.5 bar after 30 min.
This test the pump check valve and injector seating ...
There is also a flow test that can be done to assure vol, but that is a different test at the same port[ not a pressure test]
Bar conversion to PSI is 14.5
As you can see , with these different test, one get a wider range of diagnosis...one can deduct pump, bad filter , leaky injectors, bad reg, etc....