[Coachg]

1984 When the fan is turned on and any of the A/C, Heat or defrost options are selected (the air temperature is as selected) the fan blows through all of the outlets. I replaced the vacuum tank but the "door" that close off the other passages do not respond, air still flows out of all the outlets. What else can I check?

[toobroketoretire]

Originally Posted by Coachg

I replaced the vacuum tank but the air still flows out of all the outlets. What else can I check?

We need a lot more information before we can help you; like which year and the rest of the details. Are you saying air flows out of all your vents even when your heater and A/C controls are turned off?

[Slicktop]

Check the climate control panel to make sure that all the connectors are hooked up/plugged in behind it. Check vacuum lines. Can not be more specific since I have never had that particular problem with my C4.

[Hotrod]

Check for leaks on all the actuators, they are vacuum controlled. The actuators divert airflow to the different outlets depending on which mode of operation you select. I believe there are three in all. Actually, its best to start at the vacuum source and trace the vacuum lines thruout the system. Start at the vacuum tank under the hood and then to the control head at the HVAC control panel and then to the vacuum actuators.