Clean first....I bought a Janome 3160 used....the owner NEVER cleaned the bobbin/race hook area! It was really in bad shape and not running well. My luck..she reduced the price. I took it home, cleaned the Bobbin area, put the machine on a large towel on the kitchen cabinet, took the bottom off and cleaned some more, oiled the wick and needle bar only.....purrs like a dream.......try this first. If it is the side to side needle bar not moving in the zig zag mode (decoratIve stitch mode), grab the needle bar with machine off the try and move sice to side...if hard to move, oil the mechanical portion of the bar and work it back and forth......if this is not working, then take to your dealer. Best wishes