Hi all,

My 86' will blow air through the front vents all the time, regardless of wether the air is directed toward the floor or the defrost. I can feel some air going to the floor and defrost when I select heat and defrost (E86 electronic HVAC), but some air always blows out of the front vents.

Is this normal?

Thanks!

 

Check the vacuum line that's by the distributer. It goes into the car for the HVAC and someimes it cracks.

 

Not normal

 

Thanks guys!

I have temp control, and as mentioned, if I select heat, the floor vents turn on, and if I select defrost, the dash top vents turn on (and the floor vents turn off), but there is always some air coming out of the front vents.

Looks like I am taking apart the interior!

 

You don't need to tear out the dash - yet. Vent doors are controlled by vacuum and the solenoids are mounted on the lower half of the HVAC plenum to the right of the accelerator. Remove the Driver's side Hush Panel to access them. GM usually follows the following color scheme for each vacuum solenoid hose: Blue - A/C vents; Red & Tan - Defrost (2 hoses as the design sucks the Defroster door shut when the system is off or when Defrost isn't requested and sucks it open when Defrost is selected) and Pink - Heat. Remove the hose(s) from each valve and use a vacuum pump to operate each solenoid. They should hold 10 inches of vacuum and the door should move; ie, the air should flow out of the correct vents. If so, put the Controls to each setting and verify vacuum at the valve. If it's not there, examine each hose and the harness connector at the Programmer (Electronic Air) for damage. The Programmer is a postcard size box which electronically switches the vacuum source based on inputs from the Controls and is mounted fairly close to the Solenoids. Note: don't be alarmed if you get some flow out of the Defroster and Floor Vents when a/c is selected. At some point, GM designed it that way to keep the windshield defrosted and the floor cool - should be outlined in your Owner's Manual. You will also find another hose out of the Programmer - orange - that runs to the outside air solenoid on the passenger side Kick Panel and is used for Recirc - Auto 60. When requested, that forces inside air through the Evaporator to promote better cooling. The other hose - Black - is the source.

 

Is that the panel that covers the bottom of the dash, or the panel that runs along the driver's side of the transmission tunnel?

 

Bottom of the dash above your knees.