well, I have a tial 38mm, I was using a kinetic manual controller, hooked to the top tof the WG, and a manifold vac. source.. when I installed the avcr, I conected the top of the WG to the COM, then installed a second nipple on the side of my WG to connect to the NC port. This was also T'ed into a vac source just like the instructions say. I also tried no "T" w/o vac to NC port. I havnt tried to the NO port.. the instructions say not to use this one for external WG though.. so, I am still at a loss. It's funny because the wiring was such a pain to figure out, I thought for sure the vac lines