Hello I have a 2008 Mercury Grand Marquis LS.
I have approximately 65000 mile.
And just started having problems with the air.
It does not matter where I put the controls (Auto,Max-AC,AC,ect...)
Or even where the fan is placed the air will be all over the outlets.
From the defrost, floor, rarely through the dash.
What can I do to fix this?
Thank's for any help.

 

Buy a new heating/air conditioner control from a Mercury dealer for 500 to 600 dollars, I once got one from a salvage yard and it did not work, so to the dealer I went and bought a new one.

 

I'll place my bet on your blend door actuator being the cause.

It is a fairly cheap part, but unfortunately takes removal of the entire dashboard at several hours labor. Expect this to be a $600 repair.

One of the few known weakness of this car that just was never corrected.

Let us know how you make out, Bill