I have air coming out of my defrost and heat, but not hot air, but have hot air going to the rear heat. 2003 GMC Savana

SOURCE: 2005 GMC Yukon air conditioning

this just happen to me 2005 denali; dead battery in the morning, replaced it...and I have cold on drivers & screaming hot on passenger...is there a fix posted....& I just dont see it?? what gives?

SOURCE: 1999 gmc safari van upper vent

Check under the hood for deteriorated small vacuum hose coming off the intake over to the heater box area.
Repair the vacuum hose.

SOURCE: 2004 GMC Envoy; Very little air flow from FRONT PANEL

Try replacing the cabin air filter.

Colin Stickland

• 22516 Answers
• Posted on May 30, 2009

SOURCE: a/c and heater only blow air out of defrost

either a vacumn pipe is broken or the ends split so its not passing a vacumn to open the flaps,where they are and how to get to them i cant help because i have never worked on one as they are not here in spain.check the engine end first though .Look for some small rubber pipes running from the inlet manifold

SOURCE: 2002 GMC Savana 2500 Front AC warm, rear AC cool/cold

Typical symptoms of being a little low on refrigerant.