The convection fan in my stove turns off and on. It works for 10-15 minutes but then starts making a clicking noise. I removed the fan cover and found that the fan was hitting the heating coil. I was able to bend the coil back into a position where the fan blades no longer come in contact.

I though the problem was solved but the noise has returned. Now, I'm getting the clicking noise even though the blades are not coming into contact with the coil. (I again removed the cover and am able to watch the fan blades.) The noise is not constant.

Would a faulty fan motor make this kind of noise? If not, any idea of what is hitting the fan if not the coil?