When driving over a bump vehicle dies what is the problem?

I have a 99 expedition, no problems until I accidently drove over a speed bump hard. Jarred everything pretty hard. Three days later road construction road work hit semi pot hole vehicle immediately died. Service light and others came on. Vehicle would crank over but acted as if no fuel was reaching it. Mechanic replaced fuel pump and filter. Ran fine for a few hours. Drove over small curb in driveway rather gently vehicle died and everything repeated as from the begging before pump and fuel filter was replaced. Mechanic checked relays and kill switch and everything checks out to be ok. What could possibly be wrong? There isn't and twirling noise at all from fuel pump and it was just put in and ran for that few hours until it hit a small curb when gently driving over it. Mechanic believes something in between kill switch and fuel pump is wrong but not sure. HELP