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1996 Blazer AC Problem

I have a 1996 Blazer where the AC is stuck blowing floor/defrost. I know that the air flow is changed by a vacuum powered motor but I do not know where it is. The heat/cold function work fine so I know I am getting some vacuum there but the Chevy dealer ship wants $100.00 to tell me what is wrong. Any one know where these are located?


The blend air door (outlet air temperature control) is not controlled by vacuum. The air direction doors are vacuum controlled. It may still be that you are not getting any vacuum to the climate control. This is the most common problem. Start with the easier check to verify the vacuum line from the engine to the climate control before you dig deeper.

Thanks, Any idea where the vacuum comes in to the cabin? I have vacuum at the Ball but I did not know where the line came through the fire wall. Are there one or two motors to control the air direction?

Last winter the floor/defrost blend door failed on my 2000 Blazer, air was only coming out the defroster. The blend door is up in the dash between the steering column and the center console. I think the dash has to come out to get to the part. I fished a coat hanger up through the floor vents and poked around till the air flow was ~50/50 through the defrost and floor vents. Proceed at your own risk.

A few days later the dash vents stopped working. The blend doors and actuators for the dash vent and recirc setting are behind the glove box and are accessible after the glove box door is removed. The dash vent blend door is on the left, I gently worked the actuator rod to free the sticking blend door. Currently, I can switch the air flow from dash vents (AC) and the floor/defrost vents (heat).

Autozone has a repair guide for the 96 Blazer.

Ed B.