A/C blowing out of heater vents (near floor)

[Silver Fox]

Had my car out today. It is about 90 degrees, so I decided to turn on the A/C. It will only blow out of the floor vents, no matter which setting I have the control on.

Any ideas on where I should start my troubleshooting?

Rob

 

[blackmonte]

Vac leak on the hvac controller?

 

[Silver Fox]

Vac leak on the hvac controller?

I assume that might be behind the dash?

 

[blackmonte]

Check behind the glovebox colored connections, pull the hvac controller above radio check the conections behind that , and the vac ball drivers side

 

[blackmonte]

Oops sorry vac ball drivers side front fender

 

[87gnguy]

Mine did the same thing... I found that the vacuum lines going behind the motor along the firewall had a crack in one. Patched it with a piece of hose and works fine now.

 

[turbo nasty]

Hey Rob The lines should definetly be checked.
Also

Typically the defualt is defrost , is it coming out of there?

Do you hear anything vac leaking sounds the that sounds like its coming form behind teh head unit?
if so you probably need to replace this.

ROCK AUTO

Heat & Air Conditioning : A/C Vacuum Control Valve Heat & Air Conditioning : A/C Vacuum Control Valve

ACDELCO Part # 1571389 ACDELCO Part # 1571389

VALVE,HTR & A/C CONT VAC w/A/C MAN VALVE,HTR & A/C CONT VAC w/A/C MAN CONT(C60); VAC SEL 9 PORTS CONT(C60); VAC SEL 9 PORTS

Another thing that might need to be checked and replaced due to simply age is the hvac check valve
Its at the rear of the engine kinda behind/between the driver valve cover and coil pack 3 vac lines going to it.

 

[Silver Fox]

I took the afternoon off to chase the problem down. I took the HVAC unit out and could not find any problems. I traced all the vacuum lines and they were good.

So I decided to call Turbo Nasty who was installing dew sweeps on his GN. We figured out I had installed the check valve (in front of the EGR valve) backwards when I replaced some vacuum lines last fall. I turned the check valve around and the a/c vents work fine works fine now.

Thanks Turbo Nasty!

Oh yes - it was blowing out of the defroster vents and not the floor as I initially stated.

Rob

 

[blackmonte]

Cool,glad you got it fixed fast . Now you can sleep at night . I hate thinking about stuff like that until it's fixed.

 

[Silver Fox]

Cool,glad you got it fixed fast . Now you can sleep at night . I hate thinking about stuff like that until it's fixed.

Thanks. That kind of stuff bothers me too - especially since I hopefully have to drive the car across New Mexico and Texas next month. I did not want to do that without a/c!

Rob

 

[turbo nasty]

Glad its fixed dude...Hoorah

 

[drewmah]

Thanks guys. Just replaced starter and when I got everything working my A/C was blowing out the heater vent and defrost vents. Crawled around under the dash checking vacuum lines and control cables and couldn't find anything wrong. Then I read one of Silver Fox's posts and started looking around under the hood. Vacuum line from that 3 port valve had the feeder to the metal tubes unhooked. Your posts saved me a lot of time. Thanks. Drew

 

[wiseman]

My air wasn't blowing out of my middle vents, but only on the floor and thru the defroster. I did what Silver Fox said that Turbo Nasty said and checked the check valve next to the EGR and BOO?.....I did have it installed backwards. I switched it and Cha-Ching!!!! Instant air out the middle vents! Thanks you guys, instant life saver, I was about to tear the dash down again, lol

 

[turbojay]

Subscribed. I have same issue on my GN.


Posted from the TurboBuick.Com mobile app

 

[GNICETRY]

Do you hear anything vac leaking sounds the that sounds like its coming form behind teh head unit?
if so you probably need to replace this.

http://www.***********/servlet/the-404/Buick-Grand-National-parts/Detail

That is exactly what I have. Can you give me a new link? Old one doesn't work.

 

[larry33kc]

Mine is blowing half from the vents and half from the floor. Any ideas ?

 

[wiseman]

Do u mean half from center vents and the other from half is from floor vents?

Anything from top defroster vents?

Sent from my HTCONE using TurboBuick Mobile mobile app

 

[larry33kc]

No, I believe it has air from all the vents and the heater floor vents