Have you had this experience with your sewing machine?

[WendyI]

The machine sewing after you have removed your foot would make me very nervous...I'm also thinking wire short. THAT I would get checked.

I was having problems with bunching thread and discovered that I was not holding enough tension on my thread when I threaded the machine. So sometimes it would thread okay and others not. Make sure you are absolutely following your manual. I also was putting my bobbin in upside down which meant it would thread wrong and this caused bunching up also. My dealer showed me to hope the bobbin and thread as it forms a "P" then put it in. Hopefully it's something as simple as that with you as well!