1997 GMC C3500 won't start

It was running fine last week . Then it would not start as if out of gas . Added gas - no help . Removed air filter and it started and ran good . Next day it would not start - removed air filter and again it started . Ran most of the day and then didnt start . Afriend was wiggling wires on air flow sensors and it started and ran good all day . Next morning wont start . Changed air flow charger sensor near air filter - still wont start . When I first try to start it it will sputter and then act as if it is getting no gas . Help .