was welding on some .100 thick aluminum today and could not strick an arc without touching the materail ,then it would weld just fine and when i stopped had to touch again to get the arc started again,gas was at around 7 lpm 3/32 lanthanated tungsten,i even tried to strike arc on my ground clamp to make sure it was not a grounding issue, still same thing happened also my gas has been staying on when i am done welding almost like i have my post flow on,but i dont,then sometimes when i push on my pedal again it goes off.