Could be a break in the cord, just where it goes into the foot pedal or into the machine. You can tell if it has a break by pushing the pedal down, then wiggling the cord at both ends. If the machine powers up sporadically, there's a break in the cord. Sometimes, the cord can be shortened and re-wired at the foot pedal end, to fix the problem.
Could also be the motor brushes have worn out, or got jiggled out of place with the move. The motor brushes are under caps on the motor that unscrew. Pull a motor brush out and see if they both need to be replaced.