Air may not blow out of the vents due to several issues, including a clogged air filter, which restricts airflow. Other potential causes include a malfunctioning blower motor, blocked ductwork, or issues with the HVAC system's thermostat. Additionally, a closed or partially closed vent can also prevent air from circulating properly. Regular maintenance can help prevent these problems.
The most likely cause would be a vacuum leak at the rear of the engine or a defective selector switch.
Check the cabin filter if applicable.
A plugged cabin air filter could cause poor air circulation coming out of the ac vents but you would still hear the blower motor running.
heater on at idle and will not blow warm air. when moving it blows the warm air from the vents. what will cause this
Any of the following can cause this......... 1. Bad a/c - heater controller.. 2. Bad a/c - heater controller inside door operation.. 3. Bad, broken or cracked vacuum line/lines..
The flap that directs sir to the selected vents is jammed or broken...or the switch that controls it is.
The blend door actuator may not be working.
The air of your Chevy trailblazer 2004 blow out of the front vents when the air conditioner is on because the air condition is faulty and it needs repair.
The HTR RR switch in a Kia Sedona determines which air vents the air is blown through from the rear heating. When it is pushed in, the lower vents blow hot air, and when it is not pushed, the roof vents blow cold air.
If the air vents of the Chevy trailblazer 2004 are not blowing air, have the fuel pump checked.
Possible blockage in the rear air units expansion valve. I just replaced mine for the same reason.
vacuum leak the vacuum reservoir is below the left head light, check the hoses