Fuel supply problem I think

[Kirkwood]

I have a 05 v50 it only starts for a few seconds and then dies I have checked the fuel rails for presume and it is very low I check and it is getting continues fire to plugs.is it posable that the fuel pump is not working full þime or is there a relay or regulated that could be coursing this problem I can't find anything on this any help would be much appreciated

Thanks in advance completly frustrated