my 1996 blazer runs great but if i shut it off and leave it sit longer than 10 seconds i will have to pour a little gas in throttle body to get it to fire. when i turn key forward i get fuel in rail but for some reason the fuel doesnt get into injectors until i put some gas in throttle body. any ideas???.

 

You likely have a fuel leak somewhere in the system. A fuel pressure test following the requirements found in the appropriate link from my signature will tell you where the leak is. Another possibility is that the pump isn't always turning on properly.