On Sat, 16 Aug 2008 11:05:46 -0700 (PDT), jcage@lycos.com wrote:

>I have a 92 Pontiac Grand Prix and suddenly, the 'vent' switch doesn't
>shift the air flow through the vents on the face of the dash. Blower
>only blows through the floor or defrost. Is there some sort of relays
>that may be acting up and not allowing this to switch properly? The
>heat control switch on the dash indicator lights function properly but
>the actual switching of air isn't taking place. This problem seemed
>to coincide with when I changed the car battery but that may just be a
>coincidence.
>
>Summer heat is such that the AC just can't get enough cool air into
>the car through the floor vent so I'm anxious to get this fixed.
>thanks very much for any pointers...
>
>John


The back of the heater/AC control has wires and a vacuum switch and
maybe a cable. The vacuum switch has fallen apart. It's held in by
a "speed" nut affair and the cheap plastic has let it go. If you can
find all the pieces you may be able to reassemble or find another at
the wrecker.

P