Cars & Trucks Logo

Related Topics:

Posted on Feb 02, 2018
Answered by a Fixya Expert

Trustworthy Expert Solutions

At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.

View Our Top Experts

Have a 1971 corvette with factory air,,the air works but weak,,the floor vents don't open on vent.I assume it's vaccum operated,so how does it work and where is the box which switches the air flow,,from bi- level.dash,,and floor vents located ,none of the service manuals I have show it ,,thanks

1 Answer

David Harrelson

Level 3:

An expert who has achieved level 3 by getting 1000 points

Superstar:

An expert that got 20 achievements.

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

  • Chevrolet Master 5,456 Answers
  • Posted on Feb 02, 2018
David Harrelson
Chevrolet Master
Level 3:

An expert who has achieved level 3 by getting 1000 points

Superstar:

An expert that got 20 achievements.

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

Joined: May 06, 2008
Answers
5456
Questions
17
Helped
1102103
Points
15442

Most of these components are located way up under the dash and may require removal of the entire dash to gain access. Any vacuum leak can cause this problem, as can a bad vacuum check valve, so check all lines using a vacuum gauge before you tear into it.

5 Related Answers

A

Anonymous

  • Posted on Jul 19, 2008

SOURCE: 2004 Ford Crown Victoria no air flow through main air vents

Chances are the electronic/digital HVAC control unit is bad. This same problem happened to me and I had to replace the entire unit. The dealer wanted to charge $800 for just the part! After I freaked out on them, they found a used one for less than half. Sorry, but there's no easy fix here.

Ad

Anonymous

  • 1 Answer
  • Posted on Jul 22, 2008

SOURCE: There is no air flow

You need part GM Part number 89018675 or ACDelco 15-73596. The Mode Selector Actuator. What happens is the part is a CHEAP part POORLY designed and when it goes to turn the flaps inside the HVAC unit its the plastic gear slips instead of turning the flap!!!

Just to forward you you might want a deal to install this art for you unless your good at fixing your own vehicle, because you need SMALL sockets and a lot of patience to get this part in!!!

The part is ALMOST directly above the steering shaft for your steering wheel, so theres a lot you got to remove before you will even see them!!!

I only recommend you to have a dealer put this part in for you, unless you have your own service manual!!

Because there is 5 of these darn things and if you pick the wrong one you will have to do it all over again!!!

3 on the Drivers side and 2 on the Passengers side!!

But replacing this part SHOULD solve all your problems!! AS it did for me and i was having the same issues as you have described!!


kn1ckfan

Robert Kerman

  • 11 Answers
  • Posted on Mar 09, 2009

SOURCE: HVAC vent selector does not function. Air flow is

THe blend door seems to be stuck. When you change settings from defrost to floor air or, vent, the blend door opens and closes directing the air to the place you want it to go to. I have had some success spraying a lubricating oil such as WD40 under the dash on the blend door. You need to get under the dash with a flashlight to locate it. It looks like a flap. Spray it with a couple of shots of the WD40. Go easy on the spraying as you may be inhaling the fumes. Keep the doors and windows open to minimize the fumes. Wait about 1/2 hour and try the A/C functions. (defrost, floor, vent air)

Stan R

  • 37 Answers
  • Posted on Mar 13, 2009

SOURCE: PROBLEM WHEN SELECTING THE DIRECTION FOR THE AIR

Sounds like you have a supply vacuum problem. When you lose supply vacuum to the control head it defaults to defrost.

Anonymous

  • 150 Answers
  • Posted on May 08, 2009

SOURCE: AIR FLOW STUCK IN DEFORST VENT WILL NOT SWITCH TO FLOOR OR AC VEN

The "MODE" door works off of an electric motor.

Ad

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
2answers

AC doesn't blow from dash vents.Blower will not switch from floor position.

NEED TO HAVE YOUR TEMP CONTROL UNIT CHECK FIRST. ONE OF THE VENT DOORS ARE NOT OPENING UP
4helpful
1answer

Our 1998 buick lasabre air condioning will not blow out vents. everything works, but it wont blow out vents. it will blow on window vent and blows on floor vent.but the middle vents will not blow out.

ck to see if your vaccum hose if broken at the engine vaccum connection, it may have a vaccum hose split or a bad vaccum switch/actuator, if it has manual a/c, if it has electronic a/c then your mode actuator is not working.
1helpful
1answer

1981 corvette air conditioner ventilation

hi

this is because
1.there is some blockage in the line comin up and to sides.
2.the selector switch is not properly functioning. the flaps got stuck and it may allows only air to pass through the floor vents.


please vote me if my answer was useful to you.
0helpful
1answer

Air stopped coming out of teh face vent

you have a blend air door problem. if the control head is working properly then you should look behind the glove compartment for loose vaccum lines or wires.
1helpful
1answer

2002 Durango heater controls. The directional

if it works off vaccum you have a vaccum leak
1helpful
1answer

Air keeps changing from upper vent to floor by itself

The vent control works off vaccum from the engine. I would say either the vaccum line is leaking, or the switch to adjust airflow is going bad.
2helpful
1answer

Air blows out floor vents only. Blower is working and fan speed switch working

Air blows out floor vents only. My friend your Auto A/C system is control by Vaccum. Open up your hook and look for a black vaccum hose size 1/4" link into your fire wall. see if the hose is crack or broken. The other way to bypass the control: I can show you very detail by provide me the year I can get you the diagram for it. [email protected]
4helpful
1answer

Air only blows on floor with very little coming out the defrost or regular vents.

Hope you have the same set up, sure you do. You may have either crossed your vaccum lines or when you were putting your heater/ac box back together or you may of pinched the vents somewhat closed. Cycle through the different zones to ensure the vents are moving as your are selecting (defrost, floor, ect...) If you think the vaccum lines are correct then you may have a reassembly issue with the Heater/ac box. I had the same problem with my 2000 Dodge Ram 4x4. Use the KISS rule "keep it simple stupid" start with the vaccum lines and all your wiring to the motors, make sure everything is plugged in. Hopefully you'll find it there before going back into the box again.
0helpful
1answer

Air will not blow out the vents

Sounds like the hvac doors are not moving when the dial is switched. These are usualy vaccum operated and the switch is under the dash behind the glove compartment. You probably need a service manual to know which lines run the door that controls where the air comes out, but you might only have a vaccum line pulled loose.
1helpful
1answer

No air flow from defrost vent on my van.

Could be a vaccum line leaking not changing the vent flap to defrost
Not finding what you are looking for?

93 views

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

ZJ Limited
ZJ Limited

Level 3 Expert

17989 Answers

john h

Level 3 Expert

29494 Answers

Thomas Perkins
Thomas Perkins

Level 3 Expert

15088 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...