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1990 corvette air cond blows air out the defrost

I love my Chevy Chevette!
Posts: 1
Joined: 04/14
Posted: 04/01/14 08:32 AM

1990 corvette most out the air is going out the defrost outlet and very little out the dash outlets. I have the auto style air cond. Any suggestions as to what the problem might be?

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V-6 Camaros rule!
Posts: 31
Joined: 11/13
Posted: 04/01/14 09:31 AM

C68 is the automatic climate control.... and is shown on the lower half of this image..  and its still vacuum controlled...


image #17 thru 26 exist on both styles of climate control..  #18 is the vacuum reservoir and is stashed way up in front of the left front tire..

you can see more of the vacuum system in this image...


you are going to want to start replacing vacuum hose...
you can buy a roll of goodyear 65111 which is under 20 bucks usually
Goodyear Vacuum and Windshield Wiper Hoses #65111
Windshield Washer Hose, Vacuum Tubing, Black, Rubber, 5/32 in. I.D., 50 ft. Length
that will give you enough for a life time.. and you will want probably 8 or 10 foot of the next size up.. 65112 7/12 vacuum hose...

why spend the time looking for goodyear.. so you don't have to replace it again in a few years.. gates vacuum hose is just as good.. anything else.. don't bother in my personal opinion..  

please.. have a box cutter.. a pair of sharp wire cutters..

select ONE section of hose at a time..  slit the ends of the hose to make it easy to remove from the plastic hose barbs.. remove that section.. measure it next to the new hose and cut to the exact same length..  install that section of hose..

move to the next section..  slice.. remove.. measure.. cut . install.. next..

you are going to find dry rotted hose.. you may find some cracked hose.. you may find you need some bigger diameter of hose.. this hose system as you see goes all the way to the brake pedal.. and over to the cruise control servo..  you won't have to replace the hose to the brake pedal.. and usually not anything under the dash board..  you may need a new check valve..

47150 Help Vacuum Check Valve Zps828e445f

is lack of vacuum your issue????? that will prevent the system from switching between the different outlets..

have i done this before.. yep..  that's why i know what to tell you..

its the first place to start.

my friend who brought over his crossfire car ask why i was not fixing stuff under the dashboard as his vents failed to switch.. i was up by the left headlight.. i am.. i still recall the day he picked up his cross fire car the first time after i fixed it.. i said .. go out and punch it hard.. he started to accelerate  slowly.. i yelled HARDER.. he did... and i could see the smile build on his face as it pushed him back in the seat.. what a great day that was..  his car had been hobbling along for years..  

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V-6 Camaros rule!
Posts: 31
Joined: 11/13
Posted: 04/01/14 09:33 AM

oh.. a dreaded double post..

sorry peak... danica is just hot..


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