According to Ford's maintenance site, I'm supposed to be replacing this thing, but I have no idea what it is, what it does, or where I can find it to replace it. I tried looking in Chiltons but it isn't even mentioned there. Is this thing even important enough to bother with?

TIA


1995 Contour GL 2.0L ATX- Teal Metallic+Grey Int. Brown University, Class of 2008!