Check the floor heat vent and defrost to see if air comes from them. The vents will be vacuum controlled and a vacuum leak will make the vent doors divert air to the wrong place. Check the entire engine and climate control systems for a vacuum leak.
If the air vents of the Chevy trailblazer 2004 are not blowing air, have the fuel pump checked.
Check for a vacuum leak -sounds like it is starving for vacuum and reverts to the default position
yes
i had the same problem .. i got frion and put it in and it worked fine
what could be wrong is you might have a vacuum leak somewhere or something is disconected in the dash that switches to the vents. I had a problem with my 97 blowing air threw the floor and it was a little vacuum leak that caused it
27Jun09: I had this problem on a 1999 Lumina LS. The answer is a vacuum leak. Mine was near the vacuum canister that controls the vents. The hose was replaced which (with labor) cost about $100. Just got it back and it solved the problem. DRB
I have the same problem, and looking for answers. Please help!
Probably a vacuum leak. Check under the hood for a cracked or pinched vacuum line.
Your AC might be blowing out of dash vents on the windscreen as you might have turned the knob to that particular mode. It is also possible that the vent mechanism might be out of order or broken.
The heater core is leaking coolant.
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If central air conditioner turns on but is not blowing through the vents, check the filter. If it is dirty, change it. Change the thermostat into cool, this will defrost the air conditioner.