rough idle when cold
 

So, to bring everyone up to speed. 91runner 3.slow auto, just replaced timing belt and all associated pulleys and replaced head gaskets and all upper end gaskets not more then 10 miles ago.

When starting the truck cold it wants to die out, if I hold constant on the throttle at 1200rpm it will rev up to 1600 and down to 600rpm over and over.
I also noticed that when its running rough it has almost no vacuum ( no breaks) at all.
2 to 4 min later its fine even though the temp gage hasn't moved at all.
Any suggestions?