I tried to research what the torque specs are for the intake manifold for our 16 XC90 T6. Does anyone know where to find torque specs and sequencing?

 

If you can't find a defininative source such as VIDA you can try calling a volvo parts store. If I were to guess - I'd expect something in the 15 ft-lb range. As to a sequence, I'd start in the middle and work your way out to #1 and #6. After that you can spray around to check for any air leaks and adjust according.