2002 Chevy S-10 6 cyl Four Wheel Drive Manual 152000 miles
My heater/ac selector switch is not actually changing where the air comes out of my dash. At first the switch made a hissing sound which indicated a simple bad switch. I swapped switches with a 1996 S10 I have (same part) and the hissing stopped, but still no switching of airflow. The switch I put in from the 96 worked - I tried it 10 minutes before I pulled it to verify functionality.
When I feel the vacuum plug that actually plugs into the back of the switch, I can feel a vacuum draw on the black hose (if that means anything). However, when I remove the glove box and feel the hose that goes to the vacuum cylinder that controls where air actually is directed, there is no vacuum at that line that I can feel.
I can't see where that line comes from. It isn't straight out of the switch. It comes from behind the ash tray, but I can't see where.
If there was a vacuum diagram for my truck that I could see, that would be great. Or if somebody just knows what the problem might be that would be great too. Thanks.