I have a 2 year old Brother 9000. It has worked hard and well for an hour or two each weeknight and up to 20 hours of sewing on weekends. For a while now when I start to sew it takes off with large basting-type stitches. I stop, rip (just takes a pull) turn off, turn on, try again and it's fine. Been doing that a couple of weeks now. Tonight it did that, but I could never get it to fix - kept up the basting stitches. THEN it stopped advancing fabric - just stays in one place and sews.
I've rethreaded top and bottom, taken apart and cleaned, changed needle, feed dogs down then up, turned off, turned on, changed stitch length up and down, and changed tension. Nothing changes.
Now what? I don't even know where a service place is around me that works on these.