Originally posted by 85crownHPP
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Originally posted by 85crownHPP
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Originally posted by 87gtVIC
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The black hose connects to the blower housing. It doesn't actually go through the firewall. Its what causes the sensor to pull air from the cabin. Inside the sensor, it passes air from the blower through a venturi to create vacuum. This draws in air from the cabin through the small slot in the trim. If the hose isn't hooked up, or if the slot is blocked off the sensor won't sample any cabin air. This causes the temperature to not auto-adjust as it should. it will cycle from too hot to too cold instead of stabilizing.
And yes, that sensor is the vacuum regulator. Thats why the system goes all stupid when the blue thing goes bad, its the man behind the curtain so to speak. ATC is remarkably easy to troubleshoot once you understand how it works. Most of the problems are going to be that blue thing, or clogs in the tube so it cant sample air. The lever in the dash has little to break, and vacuum motors basically work or leak.
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