a/c blows lightly on high

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Jul 21, 2019 | 09:43 AM

michael lake

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2nd Gear

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a/c blows lightly on high

my a/c fan blows hard and cools well but the air coming out of the vents is like the fan is on low....even on the highest setting. Seems like it should be much more air coming out of the vents at this fan setting?

Last edited by michael lake; Jul 21, 2019 at 09:44 AM.

Jul 21, 2019 | 10:20 AM

bc6152

Drifting

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From: S.E. Pennsylvania

Switch to interior recirc instead of outside air ventilation.

Jul 21, 2019 | 10:22 AM

michael lake

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Already tried that. No difference in volume of air

Jul 21, 2019 | 03:02 PM

mstromquist

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From: BEST Corn-Nation

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Does it sound like it's blowing hard air but it's not coming out of the vents? If that's the case check and make sure it's not being diverted to the floor and defrost vents at the same time. If it is then you most likely have a vacuum leak someplace.

Jul 21, 2019 | 06:43 PM

Vetteman Jack

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Moved to C5 Tech.

Jul 22, 2019 | 10:03 AM

K-Spaz

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First thing I'd be looking at is the blower motor resistor that sets the fan speeds. They do burn up over time. They're not real cheap as I recall. It's under the dash in the passengers foot well right beside the fan. Held in with 2 screws and roughly about 3-1/2" by 1-1/2" or so. Typically you can see if it's burned up because there will be traces on the board that are smoked. When mine died I could smell burnt electrical parts in the car.

Jul 22, 2019 | 03:29 PM

Bill Curlee

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From: Anthony TX

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If the blower motor changes speeds when you commant it to but the air delivery is weak, you most likely have an AIR BOX Damper door issue.

ALL the damper doors that control where the air comes out are vacuum operated. They use vacuum actuators to shift the damper doors. IF, you have a vacuum failure, NONE of the damper doors are in any specific position and you have air flowing out of ALL the dampers at the same time. You can check.

Feel the defrost, middle vents and the lower floor vents. If you select mid level,,, ALL the air should come out of the MID level if the actual damper are working.

The vacuum starts at the back of the intake manifold, runs down to the passengers fender well area and then goes to a reservoir and then goes to the different systems. That feed goes to a AIR BOX Vacuum control module where electric signals turn on solenoids to allow air to go to the proper dampers.

Bill

Jul 22, 2019 | 10:11 PM

Tusc

Running Guns & Moonshine

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From: CT

I recently resolved a similar issue with mine. Having initially confirmed the vacuum lines were good... I later realized that the factory female connector behind the intake had cracked under role of its "ribs." I replaced it with a section of rubber and zip tied it like a sir. The vents now shift readily between settings, it blows hard and best of all it blows ice cold.