it idles good, but stalls when i go to drive, how do i fix this?

I have the same issue with my 85 sierra, the lower i put the idle the less it stalls out on me, but the truck idles hard..and you would think it would stall out more with lower idle..i replaced every thing as well, thinking it was a fuel issue..it is bad on taking off on hills so muh that i kep light presure on gas at stops on hills..i just keep tinkering with the idle

check the gasket under the tbi unit for being blown.get some choke cleaner and spary around the bottom of the tbi unit and if the rpms change it's probably blown. also the ose going to the map sensor if soft replace that as well as the pcv hose.that's a common cause on these.