93 e150 cutting out random

i have a 93 e 150 with a 4.9 engine ,i am goin nuts tryin to figure out this problem..the van will start right up ,idle is fine,,then after driving it ,it cuts out,,random distances ,,also will start right back up after waiting ,,some times a minute sometimes much longer once again random..i changed the filter,,,and tried takin off gas cap for vapor lock,not the problem,i see this problem posted all over the net ,but no one really has a solved answer,,any ideas greatly appreciated ,,,thanks all