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1986 A/C Problem

Old Jul 18, 2011 | 08:11 PM
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Default 1986 A/C Problem

I have an 86 and the air blows very strongly out the defroster, not so strong out the normal vents. The cruise works so its not the vacuum hose. I am stumped. Please help?
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Old Jul 18, 2011 | 08:45 PM
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Originally Posted by lespaul4563
I have an 86 and the air blows very strongly out the defroster, not so strong out the normal vents. The cruise works so its not the vacuum hose. I am stumped. Please help?
what else CAN it be?
Vents are vac actuated.

go back and look at your vac hose routing under the hood. Look real close at the driver side of the dist right under the edge of it. Follow the lines both directions..both of them.


If that is as it should be, and I'll let you see it and decide, the opt 68 elec air control has a programmer that rarely fails. You really do not want to go mess with that anyway.
If its manual air the control cable is a good bet.

The best interior option would be a bad pot. You have to pull the dash pad and maybe some bezels to get in there to see. Pull lower dash panels to find the 2 vac lines that are mixed in with wire harness loom. Chances are you'll not need to do all that..
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Old Jul 18, 2011 | 08:50 PM
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Look above the kickpanel on the passenger side . There is a vac diaphram. See if it operates when you switch from AC to defrost. Try moving it by hand. Mine got stuck a few years ago and it just took a touch to get it working.
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Old Jul 18, 2011 | 09:10 PM
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Diaphram? Where? I'm only 16. Sorry for my lack of knowledge haha
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Old Jul 18, 2011 | 09:15 PM
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Originally Posted by JackDidley
Look above the kickpanel on the passenger side . There is a vac diaphram. See if it operates when you switch from AC to defrost. Try moving it by hand. Mine got stuck a few years ago and it just took a touch to get it working.

Read the first sentence.
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Old Jul 18, 2011 | 09:21 PM
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Originally Posted by JackDidley
Read the first sentence.
Does it have an orange tube going to it?
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Old Jul 18, 2011 | 09:31 PM
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Yes. Orange tube = vacuum line.
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Old Jul 18, 2011 | 09:34 PM
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It's not doing anything. What is it supposed to do?
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