You might still have one under the hood. All the cars left the factory with one there.
FWIW, if you have vacuum at the climate control panel, you need to focus your attention on the vacuum motor that switches the airflow from the defroster to the lower plenum.
Stick your head under the dash by the accellerator and look straight up. You may need to remove the lower dash panel below the steering column to see it. Ours had the motor arm become disconnected from the lever attached to the door. I was able to just snap it back on.
Others have had this motor's vacuum line come loose. Another thing to check.
See for example:
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=616684&page=&view=&sb=5&o=&fpart=1&vc=1Steve
