this pickup is hard to start but turn key off once or twice it starts some times it stall like it is not getting gas or air than it might not do this for a week or so it is getting were it blows a little smoke out when this happens and i noticed it smokes a little in 4 or 5 gear going up a hill than it stops and is fine thanks

 

check engine light flashing or staying on? codes? Could be idle air valve sticking or any number of things...