Chevy Astro AC/Heater Blower Vent con...

Chevy Astro AC/Heater Blower Vent control not working

Posted in the Chevrolet Astro Forum

First Prev
of 11
Next Last

Berkeley, CA

#1 Oct 23, 2006
1998 Chevy Astro. Suddenly AC/Heater vents don't blow except for the defroster vent on the dash. The control switch operates to turn on/off AC, but will not select the different blower vent configurations. Stays on windshield defroster blower vent.
Bob Vick

Hancock, MD

#2 Oct 26, 2006
Did you check vaccum line from the vaccum reservoir to the motor and then to the controls sounds like broken vaccum line to the reservoir

Alexandria, VA

#3 Dec 8, 2006
[quote] Did you check vaccum line from the vaccum reservoir to the motor and then to the controls sounds like broken vaccum line to the reservoir [/quote]

Bob, I am having the same problem.

Where do I look for the vacuum reservoir? Where do the lines start and end? That will help me trace them.


Calgary, Canada

#4 Jan 2, 2007
I have the same problem aswell... I did some looking around online and this is all I could come up with... not sure if it's accurate info, but maybe it will help, good luck.

"Your problem is located where the rubber air inlet meets the engine throttle body.
Look under this rubber inlet and you will find a black plastic vacuum line.
It has a hole in it or is just falling apart. Replace this line from the
intake manifold to the tee up by the A/C

Gaithersburg, MD

#5 Jan 4, 2007
all of ya'll is tripping lol i have a 94 astro,,if its blowing out the defrost just take the heater control panel on your dash witch selects the heat and air, take that off and theres a vaccum hose at the bottom left side of it,make sure thats connected, also theres 2 connectors that belong on the panel make sure those are connected..I believe you'lls problem will ly right in that ac panel...try it

Miami, FL

#6 Jan 26, 2007
delonte is trippin it was under the inlet

Regina, Canada

#7 Jan 27, 2007
hi read. its definetly a broken or loose vacuum line.. follow the lines starting at the controls to their destinations.. sure this will fix it...

Since: Feb 07

North Port, Fl

#8 Feb 7, 2007
I had the same problem and found out all my vacuum hoses had dry rotted and one of them had broken. Therefore had them all replaced

Toronto, Canada

#9 Feb 7, 2007

Toronto, Canada

#10 Feb 7, 2007

Westminster, CA

#11 Feb 11, 2007
The vacuum accumulator is a black plastic McDonalds Playland sized ball located way down low on the right side near the right front sway bar bushing. My hose rotted here and across the top of the engine from the driver side manifold to the AC tee. Replaced it all.

Midvale, UT

#12 Feb 25, 2007
I'm having a couple of different problems and your comment about the vaccuum accumulator is making me wonder.... my blower won't blow and if I'm on the highway and go over a bump I bump a lot harder then I used to. Since they are close together, is there any connection in the front sway bar bushing and the accumulator?

United States

#13 Feb 27, 2007
Well first of all does your blower work when you place the selector to your defroster/windsheild. If so then it is your possibly your vacuum hoses which have dry rotted and broke.

The bumping issue could very well be your idler arms gone bad plus while you're at it check your tie rods just FYI.

I've had both issues plus replaced the rear shocks

Hope this helps out

Midvale, UT

#14 Mar 5, 2007
My husband thinks I'm crazy and that the vacuum line can't possibly be the answer. For some reason I can't seem to find my post when he's staring over my shoulder. I used to have the same problem, where if I hit a bump the blower would turn on again. The defroster doesn't work, which is the biggest problem. So I'm assuming I can rule out just a broken line. The $5 fix isn't in my future. I guess I'll have to take it in if I want to have the tie rods checked anyway. Thanks so much for your help. I really appreciate it.

Mankato, MN

#15 Mar 26, 2007
Ok this is what I have. I have a 1999 chevy astro with a Waldoch conversion. First off the ac/heat blower only works part of the time sometimes if you slam the door or hit a bump just right it will work. Second issue-I cannot get the rear blower to work at all. Any help would be VERY much loved!

Raywick, KY

#16 Mar 29, 2007
I had the same problem w/a 1995 Brevada. I found that the blower motor would not kick on until you bumped it. I would have to bump it when I first turned on the a/c. Im not sure where the blower motor is on a Astro Van. So you might want to locate the motor and just give it a little bump after you turn the a/c-heater on.

Dallas, TX

#17 Mar 30, 2007
that's GM for you.. you have to hit, bump, smile and do the rain dance for things to work !

Dallas, TX

#18 Mar 30, 2007
ok everyone. check the plug right behind the swicth on the panel. Just pull the little square thing, check the plug...probably melted and that is for the rear blower.
for the front blower, if the blower works, check the relay that is located behind the water expension tank, or overflow tank. check the plug there as well as the ground gets so hot that it melts as well. you may need to bypass the plug and ground the relay directly top the body with a bigger wire which is what i had to do. so check those plugs... and the vacuum line as well.

Brandon, Canada

#19 Mar 31, 2007
Had loss of air flow from vents as well. One repair was at the controls themselves - broken line. Six months later loss again at vents - this time traced it to lines behind battery feeding into firewall at fuse panel. Line was chaffed/worn through by vibration agianst battery. Suspended harness with clip behind battery to prevent same problem for re-occuring. This forum was execellent source of information. Thanks to everyone elses comments. Cheers from Winnipeg!

United States

#20 Apr 4, 2007
Similar problems as above. My 94 Astro has no air blowing at all. I replaced the resistor at the heater core, and then I also replaced the blower motor. Still nothing. Occassionally if I hit a big enough pothole the heat will kick on. Where do I start as far as looking for the culprit? I can't imagine it being vaccuum related since the blower motor wont even kick on.

Tell me when this thread is updated:

Subscribe Now Add to my Tracker
First Prev
of 11
Next Last

Add your comments below

Characters left: 4000

Please note by submitting this form you acknowledge that you have read the Terms of Service and the comment you are posting is in compliance with such terms. Be polite. Inappropriate posts may be removed by the moderator. Send us your feedback.

Chevrolet Astro Discussions

Title Updated Last By Comments
Engine shuts down while driving (Mar '09) 19 hr Zahbrah 52
1997 astro not starting Aug 24 Paul jt 2
89 astro 4.3 clicking noise (Oct '08) Aug 24 starcraft 3
1989 Astro 4.3L Vortec V6 Drive Belt Routing Di... (Oct '06) Aug 24 starcraft 5
2000 astro van eating antifreeze Aug 23 rick 2
97 Astro starting problem (Jun '07) Aug 22 Carl 62
Windshield washer fuse or? (Oct '07) Aug 20 Rodney 3
More from around the web