Blower issues with 1979
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1st Gear
Joined: Jul 2025
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Blower issues with 1979
I have a 1979 with AC and the blower works fine but only blows on the floor vents. I cannot get anything from the dash vents or defrost vent no mater what setting I use. I have checked the vacuum lines and I'm pretty sure they are all good or at least as far as I can trace them. Any other suggestions would be great. Thanks
Team Owner
Joined: Jan 2006
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From: Crossville TN
Vacuum distribution manifold (or its mechanism) mounted on the left side of the heater control is damaged or needs replacement [probably]. Could also be a failed vacuum servo which operates the deflector door (which moves from floor to dash to defroster ducts).
Safety Car
Joined: Dec 2012
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From: Summerville SC
I would suggest you get a vacuum tool, like MiteyVac. Hook it up and pull a vacuum while operating your control lever. You should be able to hear doors open and close. Or you might not be able to pull a vacuum, which will then lead you to diagnose where the leak is. Hook the tool up to the main vac line, then pinch of the rest while you test one at a time. DO you have a schematic of the vac line hoses for the heater switch? That is really good to have. It will tell you which line goes where ( the green strip, the blue strip etc). If you don't have one, PM me.
Le Mans Master
Joined: Jun 2019
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From: Indiana
Le Mans Master
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From: Indiana
Race Director
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Cruise-In VIII Veteran
most likely cause, broken plastic rivet in the vacuum selector. Actually, forward, center of console on a 79. Very common problem.
Le Mans Master
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From: LONG ISLAND
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It Sounds like you need a new "BLOWER" here she is. SORRY, I just couldn't help myself .............Welcome to the forum & "CLUB C3"
