heater core "vent"?
 

i assusme there is a vent that opens and closes when you turn the knob from cold to hot. my knob is broken. but i would like to have heat and i know my heater core is not clogged. does this flap/vent exist? if so where is it and how hard is it to get to it?

if there is a section in the fsm or other pdf file please let me know.

thanks

I believe there's a motor that controls the blend door, not sure on the FD but on the FC Mazda called it the "air mix motor". It's up in there somewhere, haven't had to get to it.

Dale