marshallsmith27
OBS Enthusiast
I have a 1993 Sierra and when I get in the truck and take off once I build up enough speed theres a noise under the dash near the blow that sounds like a door that slams. Not sure where exactly its coming from since I cant drive and have my head under the dash at the same time. when it slams you can feel fresh air from outside come onto my feet. I assume its the blend door but all the stuff I see online is of the blend door actuator clicking and stuff. Its starting to get hot here and I would like to fix this soon. My AC works just fine. A few days ago I accidentally blew some leaves into the squirrel cage so no I have a reason to get under there and get those out and fix this problem once and for all. so what do yall think this noise is. it does it once and no more until you get back into the truck again later