Y yeowguy Sr. Member Sep 18, 2013 #1 Joined Jan 22, 2007 Messages 186 Likes 0 Points 16 Sep 18, 2013 #1 I have a 2008 Mercury Milan with the DTC codes P0410 and P0491. From what I have found this leads to the secondary air diverter valve. I can not find this part on the Auto Zone website. Is there another name for this part?