Hi, I own a 1995 Blazer and I have been having problems with the HVAC system. The blower motor roars and the modes appear to change but there is very little air volume. The temperature of the air appears hot enough but just not enough of it. I pulled the blower motor & checked the fan cage for any contaminents and tested all the speeds-all ok. I also found that there was quite a bit of air coming from the area where the heater hoses go through the firewall to the core. The other symptom I noticed was the mode selector switch doesn't hiss amy more to vent vacuum when changing modes. Any help would be appreciated.

 

hi my 89 truck does the same thing and i couldnt figure out why it does that but it does effect th ep[erformance =of my truck so i dont worry about it it barly blow hot air but when it gets hot it is hot. if you figure out how it to fix it let me know please
iceman_blazin@yahoo.com

 

I also have a 95 and appear to have the same exact situation, infact when I put my hand over any of the vents I can barely feel any air flow, although it defrosts the front windscreen quick and my feet get hot, just that there doesn't seem to be a huge amount of force or flow. Also there is no hissing sound eitherwhen I switch mode.
The wifes explorer really kicks out the air, infact too much.
I was thinking about taking the dash out and checking all the pipes and heater core. Italmost seems that I can hear a huge amount of air volume being generated, but its just not going out the vents or being directed correctly, maybe a pipe has come loose and dropped partially off? who knows?
If anyone has any ideas it apprears there are three of us with the same symptoms.

 

Still no fix for this? No ideas? I was just burning up in my truck today, AC full blast. The thing is, the floor vents blow out TONS of air, just the top ones suck.

 

Same question for all of you.
Do you hear hissing?
Do you have engine performance issues?
When was the last time you checked your vacuum hoses under the hood?

Sounds like a defuser door isn't working, and on these trucks they are operated by air. Vacuum air from the engine to be exact!