every industrial situation i have ever seen with a bosch ve injector pump,has a lift pump,,,except vw,,i believe this was a cost issue,,,i use a lift pump from a isb cummins,dodge truck,latemodel 24v ya know the model truck???it gives 15 psi all the time at the injector pump inlet,,i mounted it back near tank,,i have an a1,and its in the spot where a gasser would have a fuel pump,,,dont go mechanical pump,,doesnt flow near enough,,,,,,,also see people at work all the time trying an inline filter,,they dont flow either,,a little dirt kills their flow,,and thenthey wonder why it runs crappy,so try to get that inline filter off there soon