2001 Chevy S-10 Fuel System

I have a 2001 Chevy s-10 it has the 2.2 4 cyl engine.It has been shutting down on me while driving.I switch out the relays on the control box under the hood and it will run sometimes for the rest of the day sometimes just 10 miles.I bought a new relay and the same thing happens.I tightened the connections under the box and it still does the same thing.I think the fuel pump is ready to go out.But before I buy an expensive pump to put ion is there anything else that may be causing this to shut down when I hit a bump like it does?