defroster only.
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Joined: Oct 2003
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From: Southern Maryland
Car: 91 Z28
Engine: L98
Transmission: built 700R4
Axle/Gears: 3.42
defroster only.
Not sure if this should be here or the interior board but...
When I turn on the AC, it will only blow out of the defroster vents.
No matter where I select, it will not blow out the regular vents. The air does get cold too. let me know if anyone knows what might be up. thanks.
When I turn on the AC, it will only blow out of the defroster vents.
No matter where I select, it will not blow out the regular vents. The air does get cold too. let me know if anyone knows what might be up. thanks.
Thread Starter
Senior Member
iTrader: (1)
Joined: Oct 2003
Posts: 935
Likes: 0
From: Southern Maryland
Car: 91 Z28
Engine: L98
Transmission: built 700R4
Axle/Gears: 3.42
I took the top of the dash off but I didn't see anything. but then I wasn't looking for that either.
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Joined: Jul 2003
Posts: 4,803
Likes: 2
From: Grand Rapids, MI
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Inspect the vacuum line coming off of the intake. This line gets threaded through the firewall, to the HVAC control valve, where, from here, it diverts the vacuum to move the various diverter flaps. If there is no vacuum signal picked up at the main valve, they will blow at the default which is the window defog (so a safe driving evironment can be maintained.)
Look to my initial response <A HREF="https://www.thirdgen.org/techbb2/showthread.php?s=&threadid=250925">Here</A> for a little bit more detailed explanaition.
And you have to remove the entire dash assembly to access the actual vacuum lines that are in the passenger compartment. First, remove the lower consol bezel/radio bezel and remove the HVAC controls. Look for a loose or broken connection there.
Look to my initial response <A HREF="https://www.thirdgen.org/techbb2/showthread.php?s=&threadid=250925">Here</A> for a little bit more detailed explanaition.
And you have to remove the entire dash assembly to access the actual vacuum lines that are in the passenger compartment. First, remove the lower consol bezel/radio bezel and remove the HVAC controls. Look for a loose or broken connection there.
Joined: Aug 1999
Posts: 19,282
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From: Lawrence, KS
Car: Met. Silver 85 IROC/Sold
Engine: 350 HO Deluxe (350ci/330hp)
Transmission: T-5 (Non-WC)
Axle/Gears: Limited Slip 3.23's
Since this is a common thirdgen problem, you might consider a search. Much has been written about the subject.
JamesC
JamesC
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