ac only blows thourgh defrost vents?
Your vents are controlled by vaccume..........if they don't change at all then you have a vaccume line off. I would start under the hood you have one or two plastic lines going through the firewall check them............let us know
well if its a vacuum thing i probably broke it when i changed from my stock q-junk setup to a edelbrock rpm intake and carb. the only vacuum lines i have are the one to the distributor and the the power brakes. does the vacuum to the ac vents run to the carb or what? and how would i go about fixing this? just put a t splitter in the distributor vacuum line or what? its dark already so ill have to look tomorrow
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From: Houston TX
Car: 84 Z-28 Camaro, 2022 2500 silverado
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the vacume line is the one that goes through the firewall where all the heater wires go through, behind the pass side head, if the HVAC has no vacume it will only blow through the defroster
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It's the black hard line that comes through the firewall. Hook it to manifold vacuum, not the ported vacuum that should be going to the distributer. Any vacuum source that has vacuum at idle will work. (Ported vacuum has no vacuum at idle). The defrost is the 'default' location for the vents.
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From: Rio Rico, AZ 85648
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I have the same problem, but I thought it was a green gremlin like on that Midas commercial!
I'll check that vac line...in fact, I think I know which one it is!
I'll check that vac line...in fact, I think I know which one it is!
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From: Central NJ, USA
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And if you still don't get a/c thru the normal vents, there's a rubber diaphragm that diverts vacuum to different vacuum motors that could be bad. On your climate control, that lever (off/max/ac/vent/heat/defrost) spins a selector wheel that gives vacuum to the appropriate areas. There's a bit of rubber inside that spinner, if it goes bad, you've got a vacuum leak, and you only get heat/ac out of the defrosters.
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