Quote Originally Posted by Vendetta View Post
My 1999's engine started knocking deep and loud at about the ~80K mark two years ago.
VENDETTA--- Before you do anything else, you may want to simply replace the "Tension Pulley" for the Serpentine Belt (and replace the belt while you're at it, too). There has been recent discussion, that the Serpentine's "Tension Pulley" can be the primary source for a knocking engine related sound. Do a search on this forum for: "Tension Pulley"