Hello, my girl friend's son's 2000 Express van wont start. then it will, then it wont. new fuel pmp.lou, hlp?

some new wiring i'm told to and from fuel pump. i am in a wheelchair and dont have the capability to even try to figure this out.any help would be greatly appreciated. agian,get's in and wont start,1/2 hr later(in am-pm) whenever, it starts easy.and again it dont start.electrical? thank you, lou g