Fuel, oil or other fluid might be leaking into the device from another part of the engine. If this dirt gets on the fuel injector, it can lead to jerking movements while driving. Some of them may work, but the ones which don't cause the car to jerk. A stick shift requires you to change between gears yourself as you accelerate. The winding is the wrapping of wires for electric engines. If this happens in transit, it can lead to a very serious accident as you will lose all power to your engine.