Need help
 

Hi im new here and have a question my o6 duramax will not start after I shut it off if you restart it right away it will start but if you wait 10 to 15 min it will not start cranks then it feels like the filter is empty I pump it up and it still will not start but if you leave it sit for 4 or 5 hours it starts right up or you can start it on starting fluid right away any ideas would be great thanks