Ford F-250

I am having this problem with my ford f250 pick up truck fo some reson it ill die when I am driving it doiwn the road I check to see if all the pumps are going they are all shut off so I go under the truck and bang on the one pump just before the fuel filter and it starts to run again if that pump was shot why wouold the other pumps not work aswell
this is really starting to irtate me