That means just the bake element is not receiving the full 240 volts like it needs to heat fully. Unfortunately I do not have access to the wiring diagram # 31-20718 for that model to look up what components your range might have to prevent that.
- Check for bad wiring between the bake element and the control.
- Some ranges might have a safety thermostat in line to the element that could open to prevent oven operation.
- Otherwise the control malfunctioning might be the problem and it is discontinued.
If you can locate the range's wiring diagram and upload a picture of it, I'll look at it for other possibilities.