Fuel Pump Problem?

[Swift]

You know how when you turn the key and the fuel pump primes and you hear a whirring sound for a couple seconds and it stops? well I wait for the whirring to stop and then I start the car. It runs for about 5 seconds and then stalls. When I start it a second time it runs fine, but while I'm driving I can hear the fuel pump whirring loudly sometimes. Then when I turn the ignition off the fuel pump goes for about 7 seconds after the engine is completely off. The car practically floods itself while i'm driving, and I have practically no fuel economy. All the fuel lines are fine, and my injectors are good too. Would it be a blocked or faulty fuel pump? or a sensor?

The car is completely standard minus a Police ECU, it usually idles around 800rpm but usually doesnt stall.

[m3taL]

Ok dont hold me to this, but i think the Fuel pump has some kind of Bypass on the Oil pressure switch so if the Fuse blows or relay cacks itself it continues to run. i'd be checking fuses and relays.

but if it is noisy i'd say she;s on her way out iv had 3 vns now and done a fuel pump in all 3.

1st one just died and never came back on
2nd one failed a few times leading me a stray on to what the problem is then died
3rd was noisy but didnt seem to have the pressure to run the car.

i'd change the fuel filter as well just to make sure its not blocked and causing friction.

hope this helps