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AC problem in First Gen S-10

Shadowfax

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Shadowfax Enthusiast

Shadowfax

Posted
Posted
Hey guys. I have a 91 S-10 with AC. In the last 3 weeks I've developed a problem with the AC. The air has started to come out the heater and defrost vents instead of the proper vents. I have figured out that it is most likely a vaccum problem. But thats about it. Has anyone ever worked on a problem like this in a first gen and fixed it? If so can I be given some tips on where to start looking to find the vaccum leak? BTW I can also hear the little flap that redirects the air rattle every now and then like its gettin opened and closed real fast several times.  The air comes out the proper vents in the morning or evening when the truck has been left off for a long time. TIA for any help anyone can give.
Load*,8,1 Enthusiast

Load*,8,1

Posted
Posted

i'd like to know some answers as well.  my a/c blows through my vents and floor (mainly through my floor tho) and my feet get freezing while my face and upper half stay hot :flag:

 

i heard the vacuum switches go bad easy in the old chevy/gmc trucks and is easy to fix.

 

so i'd like some help to if noone minds

 

josh

  • 1 month later...
Beaux Duke Enthusiast

Beaux Duke

Posted
Posted

If it works when everything is cool then the vacuum leak is probably small and when everything contracts the leak is sealed or at least sealed enough to allow proper functioning of the controls.

 

I have a 93 and there is a hose that leads through the firewall to the interior.  It's located almost in the center of the firewall close to the distributor and a little above it.  Track it back and make sure it's not cracked.  Replace it if you find any cracks at all.

 

If no cracks are visible then the problem in in the interior and that's a major pita.  Try removing the radio to gain access to the vacuum line to inspect for cracks.  If the line checks out then it's probaly the control unit.  Not cheap.  Try here if you decide to buy a new unit.  LMC Truck

Shadowfax Enthusiast

Shadowfax

Posted
  • Author
Posted

Whoops forgot to mention guys, about 4 days after posting this I found the leak. Evidently the hose got a hole put in it by something, and oddly enough it would sometimes seal :shrug: It works now. But hey who care Im getting a new truck on the 27th lol

 

The line btw was under the hood that led to "pot" thats in the engine compartment.

Shadowfax Enthusiast

Shadowfax

Posted
  • Author
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2003 Chevy S-10 Xtreme, stepside with the extended cab, 4.3 vortec and the 5 speed stick (i dislike autos lol) beige interior, and black exterior. Its about time too. Been waiting on it for what seems like forever :cheers:
bowtie_pasta Enthusiast

bowtie_pasta

Posted
Posted

I've had the same basic problem that load is describing.  The majority of my cold air blows at the floor.  And in the summer if I don't run the AC it will let some hot air come thru even when everything is off.

 

Years ago my mechanic mentioned something was wrong, but I can't remember exactly.  Something with the air ducts not closing correctly.

 

But hey, as long as it gets cold when I need it and warm when I need it, I'll survive.  :cheers:

  • 2 months later...
dcairns Enthusiast

dcairns

Posted
Posted
I had a problem like this on my 91 S-10.  In my case, there is a vaccum line near the firewall, just above the intake manifold.  (Take off the air cleaner and look from the passenger side.)  It would come loose and then the air routing would fail and air would come out all vents.  After it had come loose for the third time, I had to put some sticky glue on the tube to keep it from happening again.
bowtie_pasta Enthusiast

bowtie_pasta

Posted
Posted

Hey I know which vacuum hose you are referring to.  I just fixed a bad leak back there.  I'm gonna have to see if it helped anything.  Where does the other end of that vacuum hose connect to?  I though maybe it ran down to the transfer case(mine is 4WD)???

 

later

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