Question about 1995 Chevrolet Blazer

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Air won't blow through dash vents under acceleration

A/C vent work fine until you accelerate or put engine under a strain,like goin up a hill

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  • dmarshallhom Mar 09, 2009

    To snipe hunter,

    Yes air blows through defroster vent. Took your advice and found a vacuum hose left disconnected from prior work by car garage.

    Thanks buddy

  • snipehunter May 11, 2010

    no problem.

  • snipehunter May 11, 2010

    does the air come out thru the defroster? if so you have a problem with the vacuum dash pots check under the hood for a can about the size of a old tin tomato juice can and make sure that the vac. hoses are hooked up and make sure that the can dosent have any holes rusted thru it.



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Posted on Jan 02, 2017

  • 1 Answer

SOURCE: There is no air flow

You need part GM Part number 89018675 or ACDelco 15-73596. The Mode Selector Actuator. What happens is the part is a CHEAP part POORLY designed and when it goes to turn the flaps inside the HVAC unit its the plastic gear slips instead of turning the flap!!!

Just to forward you you might want a deal to install this art for you unless your good at fixing your own vehicle, because you need SMALL sockets and a lot of patience to get this part in!!!

The part is ALMOST directly above the steering shaft for your steering wheel, so theres a lot you got to remove before you will even see them!!!

I only recommend you to have a dealer put this part in for you, unless you have your own service manual!!

Because there is 5 of these darn things and if you pick the wrong one you will have to do it all over again!!!

3 on the Drivers side and 2 on the Passengers side!!

But replacing this part SHOULD solve all your problems!! AS it did for me and i was having the same issues as you have described!!

Posted on Jul 22, 2008

  • 2920 Answers

SOURCE: Air Conditioning

the control arm that controls where the air should blow is under the dash you may have to move it manually

Posted on Aug 31, 2008

  • 328 Answers

SOURCE: Air won't blow through dash vents under acceleration

there should be a vacuum line running by the drivrs side shock tower that might be unhook are cracked

Posted on Apr 09, 2009

  • 599 Answers

SOURCE: A/C Blows out at feet or through defroster, not through dash

the ac blend door is out of adjustment or the the actuator is not working look behind the glove box and watch the arm move

Posted on Jul 24, 2009

  • 432 Answers

SOURCE: All Air Conditioning blows our the defrost vents

Some thing you could look at would be this. The control is usually fed by a vacuum line or small hose thats is connected to your intake manifold.
With a cold engine,look for a skinny vacuum hose that runs from the intake toward the fire wall . It should be going inside the cab and connecting to the A/C vent control.Some times the hose becomes disconnected or splits or cracks due to heat under the hood.
Thats usually the trouble.
I hope this helps you.

Posted on Oct 06, 2009

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