MIG welder problem

My old cheapo welder won't work anymore. I have 220 volts at outlet. Wire speed, 75/25 gas, ground is good. I'm getting a poor arc and the transformer is stuttering. It sounds like it wants to go but, very poor welding. Almost like I'm not getting enough voltage through the unit. Does this sound like the transformer? I'm guessing the Pri/Sec and be checked with a multimeter. Any suggestions? I know there was a member here that used to work on welders for a living. Found them @toplscuda in this thread: I've been following Mig welder
i know this is several days old, but i just went through this with my old weld pac. was within minutes of going after a new one, when i happened to bump the amperage switch. started working again. guess the contacts were dirty. been working fine since.