Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
HomeAnnouncements
Discussion Groups
By Brand
BMWChevroletDodgeFordGMHondaLexusMercedes-BenzNissanPeugeotToyotaVolkswagenOther Brands
By Topic
4x4 CarsRVsDrivingMaintenance & RepairCar AudioCollectible Cars
Country Specific
Australian ForumsUK Forums
ArticlesAuto InsuranceBuyingCars & TechnologyMaintenanceMiscellaneousSafety
DMV Resources
Related Topics
MotorcyclesBoatsMore Topics ...

Car Forum / GMC Cars / October 2005

Tip: Looking for answers? Try searching our database.

gm air condition

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
baldballdad - 25 Oct 2005 04:51 GMT
my 1993 gm van's air conditioner works but will not blow out of the vents.
it blows from the defroster and small vents in the console. I have been
told it could be a vaccum leak, where do I look for vaccum leaks. does not
matter if I change controls from defrost to heat or to air it doesn't
change the air flow
HLS@nospam.nix - 25 Oct 2005 16:13 GMT
> my 1993 gm van's air conditioner works but will not blow out of the vents.
>  it blows from the defroster and small vents in the console. I have been
> told it could be a vaccum leak, where do I look for vaccum leaks. does not
> matter if I change controls from defrost to heat or to air it doesn't
> change the air flow

Just a guess, but at least some GM's take the vacuum from a plastic
cannister,
probably located under the hood.  I would look around there.  Some of them
are rather easy to snap off the little plastic connector.  I have drilled
them out
and replaced them with brass or plastic hosenoses from the hardware store.

If it isnt at the cannister, you can probably trace the vacuum lines and
hopefully
find one cracked or disconnected.
Larry A. - 26 Oct 2005 05:49 GMT
Most definitely a vacuum connector.   The vents are switched by
vacuum-operated actuators; no vacuum, no switching.  Do yourself a
favor and do NOT pull anything apart inside the passenger compartment,
dash, etc.  It's in the engine compartment.    

Look for hoses that are loose, brittle, or worn from rubbing against
other parts.  They should fit on the connecting nipples snugly; if
not, replace the hose.  With a car of your age, my procedure is
usually to change 'em all.  You can grow gray tracing vacuum hose
leaks on an older car.  Life's too short.

-= Larry A.

> my 1993 gm van's air conditioner works but will not blow out of the vents.
> it blows from the defroster and small vents in the console. I have been
>told it could be a vaccum leak, where do I look for vaccum leaks. does not
>matter if I change controls from defrost to heat or to air it doesn't
>change the air flow
Steve W. - 27 Oct 2005 03:58 GMT
Open the hood and the vacuum reservoir is the large black ball shaped
item attached to the hood to the right of the latch area. It has one
line that connects to it. That line will go down to a check valve
mounted on a short line toward the rear of the intake manifold (pull the
doghouse cover for better access to it) On that valve is a second
fitting that goes inside to the heater controls. Check all the lines and
the valve and ball for leaks. The valve can be tested by blowing through
it gently, if you blow into the side with 2 ports air should come out
the other side. If you blow through the side with 1 port it should not
allow air through.

Signature

Steve Williams

> Most definitely a vacuum connector.   The vents are switched by
> vacuum-operated actuators; no vacuum, no switching.  Do yourself a
[quoted text clipped - 14 lines]
> >matter if I change controls from defrost to heat or to air it doesn't
> >change the air flow
superchuckles - 27 Oct 2005 09:15 GMT
actually, 93's use a stepper motor to control the ducts.  if you
a/c's controls have a digital display, is there anything flashing o
it?  that flashing will usually indicate a problem, but - like
said, on 93's, you don't even have to have the engine running to mak
the ducts change from floor, to dash, to defrost - you adjust th
controls, & you can hear the stepper motor moving the ducts.  
was surprised too, but it's true
Steve W. - 27 Oct 2005 15:16 GMT
> actually, 93's use a stepper motor to control the ducts.  if your
> a/c's controls have a digital display, is there anything flashing on
[quoted text clipped - 3 lines]
> controls, & you can hear the stepper motor moving the ducts.  i
> was surprised too, but it's true.

The 95 that I have has vacuum controls for the heat/AC. Plus a control
cable for Hot/Cold. 96 was the redesign year that included a lot of
electronics.
superchuckles - 29 Oct 2005 09:14 GMT
> Steve W.wrote
The 95 that I have has vacuum controls for the heat/AC. Plus
contro
> cable for Hot/Cold. 96 was the redesign year that included a lot o
> electronics

hmmmm, i wonder why my 92 has electric step motors that control th
vents then - my a/c controls are electronic - there are no cables a
all - the hot - cold control is digital, & you move it up or dow
on an LED type display (that will also blink out error codes whe
there's a problem).  no vacuum anything in it (unless you wanna coun
the inlet side of the fan
Steve W. - 30 Oct 2005 15:25 GMT
On a G series? That is a full sized van you have? Never seen one with
electronic controls, even the factory book shows mechanicals.

Signature

Steve Williams
Near Cooperstown, New York

> > Steve W.wrote:
> The 95 that I have has vacuum controls for the heat/AC. Plus a
[quoted text clipped - 8 lines]
> there's a problem).  no vacuum anything in it (unless you wanna count
> the inlet side of the fan)
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2008 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.