Was trying out my new 200DX appears to be a great machine . Using with a couple of different torches i have and i am having a gas problem with one torch. I have a WP-9 flex head 3/32 tungsten # 6 cup argon 15 cf ,welding some mild steel at 75 amps welds great clean bright welds very nice. Switch over to the WP-17 Torch same tungsten nozzle ect. and there is a gas problem lots of porosity in the welds dirty looking not bright. Tried replacing collet collet body tungsten ect. ????. I took the gun apart found one spot in the hose that did not look right and repaired it . No Luck still the same problem.

Any ideas