my 97' chrysler LHS keeps dieing and won't start for a long time. ?

What could be wrong with my 97' Chrysler LHS for it to die suddenly and not start for a long time? We have replaced the fuel pump and two filters. We have put it on the computer and it detects nothing is wrong. There is no check engine light on. Frequently happens one or two miles down the highway in the evening around 6:30 pm when I am going to work. I get stranded. PLEASE HELP!!