I have the acc unit in the "O" position and leave it there because it does nothing but blow hot air in any other position. the heat is coming from behind the center console with the acc unit and radio and ash tray. It is not just some heat but hot enough to be painful--so closing the vents will not really help. I will try clamping the hose to the monovalve to see what happens and also clean out all the debris under the hood (a good idea anyway) and see what I can find.

I have to drive from Connecticut back to Minnesota this week and it would be nice to figure out how to get rid of this heat.