Here's some more diagrams:
http://www.sweetillusions.org/toyota/6.pdf
http://www.sweetillusions.org/toyota/fj60_vacuum_routing.gif
The digram below is for the AC idle up vacuum circuit
I went through this same thing after I bought my Land Cruiser ('84 FJ60) years ago. Everyone suggested the "fuel issues" route, but after replacing the fuel pump, filter, gas cap, and rebuilding the carb; the problem still existed.
Time for...