Gearmaster

I have a 2001 S-10 ZR2 P/U. With the heater control selector in the feet position I still get air blowing out of the upper section. This happens wherever I have the selector switch. Is the switch bad and how hard is it to replace. Thanks Tery

rwgreen

Do you get heat from the front vents when you select front vents?

I know most heat/air systems are vacuum controlled, and the default damper setting is the defrost/floor vent. If you have a vacuum leak somewhere it will not allow the dampers to open and close thereby allowing just air from the default defrost/floor vents.

I have the same problem with my S-10, but have not found the vacuum leak yet. Also after a few months of this my system quit altogether. I think I have a vacuum leak somewhere AND either my control panel module or blower has went out.

Hope this helps a little. Maybe a real expert can provide a more detailed explanation.

Robert

Gearmaster

Yes I have heat coming out of all the vents.

Gearmaster

Yes I have heat coming out of all the vents.

dmbrisket 51

the vacume seal is most likely cracked, its a bi*ch to get to, behind the dash back by the firewall, it opens and shuts the "door" that controlls where the air can go, my old truck does it, only i cant defrost my windsheild in the michigan winter

BlazerLT

Look for a bad vacuum line going to the vacuum ball in the engine compartment.

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