Well off the top of my head at 5am.. The air flow control knob that goes to , floor, defrost, face, etc isnt working... It only switches from defrost and floor. It will not blow air out of the 4 dash vents. Has anyone had this issue? Or possibly know of a means to correct it? Thanks in advance!

 

Sounds like the blend door isn't functioning correctly. It is controlled by a diverter valve under the dash......can't say where exactly, haven't had that problem.

 

It does sound like a blend door issue, or more accurately, a blend door actuator issue.

Give this thread a read, and pay special attention to post #11......

https://www.chevyhhr.net/forums/problems-service-repairs-42/heater-problem-33767/

 

Isn't there also a diverter door? Both operate on a step motor.

 

yesterday on my way home i turned it all the way to the right, and then flicked it to the dash vents and i heard a click like it was stuck and now its working.. idk what caused it but thats what i was thinking it was, did not know the correct terminology lol. Thank you for all the help guys, hopefully this wont happen again!