AC question

[teafreak35]

Should there be a noticable difference in the airflow when the AC is switched from outside air to recirculate? In my 99 malibu, there is no difference in sound or airflow. Ideas? I just cleaned the control head about a month ago and the lights come on when I press the desired button, but like I said, no difference between the two modes.

Is there a "door" somewhere in the system and if so, where is it?

[procaddytech]

As seen from inside the car with I.P. removed:


Normally yes, you do hear a difference in the airflow when reciculate is selected. It should sound a little more "intense". In the illustration, #5 is the recirculation mode actuator. You may be able to access it from under the R/H kickpanel or by removing the glove compartment. With A/C on in vent mode, watch for the actuator to pull back and release as you turn it on and off. Check for vacuum at the actuator vacuum hose (#6) with recirculate selected and indicator lit. Also, connect a vacuum pump to the actuator and pump it and see if it pulls in and holds vacuum. If it pulls in and holds with a hand pump, reconnect the hose and try to pump it from the proper vacuum hose at the vacuum connection at the back of the control head. They are usually different colors. Sometimes the vacuum lines can get little pieces of debris in them, kinked or small holes.