I am attempting to repair a intermittently functioning (now only very rarely) burner in an electric 30" downdraft jenn-air slide in range and oven. It is the large 8" burner that is part of the remnovable two-burner module A105-8. For a while it worked on and off, now if almost never works, and if it turns on, is only on "high" with no ability to adjust the temperature. The 6" burner in the same module works just fine. I have several questions:
1. Is this likely to be fixed by replacing the burner (AP4292347) only?
2. Might other parts, such as the control knob, have to be replaced as well to restore this to functioning.
3. In addition to the element itself, would it normally be expected to also have to purchase new gaskets, nuts, brackets, etc. to get the elements off and on after a number of years of use?

This is my first use of this forum, and I don't know how to expect the answer, whether by direct email, or by just checking back on this forum periodically. Thanks for your attention to this matter.