Elna Diva sewing machine sews but stops and then starts again, like a powering down and then up. What is causing this?

So your sewing machine starts and stops sewing, like it loses power: Sounds like intermittent power, which indicates an intermittent short circuit. This may be by a wire, contact point or a terminal being dirty, burnt, worn, loose or bent out of place somewhere. Sometimes you can locate it by: 1. Visual inspection of every contact point from Plug to Motor. 2. Physically jiggling the power line ( while the motor is running, inch by inch, from the wall plug to the motor. 3. Key places to check first: (A) Any place a wire bends, (B) Any place there is a Contact Point (that means (a) Inspecting the wall plug, (b) the wire, (c) where it goes into the machine,(d) Where the power feeds the lines inside the machin, (e) Inside of the Foot Controller: Look for sparks or burnt marks; then Clean and Check all wires and contacts points in and to and from the Controller. 4. Replace any bad, weak or over-aged wires. 5. If you cannot find the fault these ways, buy a $10 buck Non-contact voltage detecter from any hardware store or Electrical parts supplier, and read the directions. 6. The sewing machine must be on, but not necessarily running (at least at first). 7. Now hold down the button on the detector as you scan along the power line from plug to motor. 8. If the detector Blinks and Beeps when it should not, or does not Beep and Blink when it should, that is the point where the problem is. 9. If you stil cannot locate the intermittent short, replace all or part of the power feed cords until it is fixed. 10. You can order complete replacement power cords for your machine from a Sewing Machine parts supplier, or you can fashion some of it from a brand-new 16 Foot extension cord. Good luck, some shorts are tough to locate when they are intermittent. It is easier to find if it goes out totally. Hope this helps you fix your electrical short. Amender, 2020-12-03#