a/c wont blow through vents

[kevinw]

Having problem with my a/c not blowing through vents.Changed heater core out before problem.Checked all vac. lines for correct hookups and no leaks either. Air blows through top and bottom vents only regardless of setting. Any ideas

 

[Snorman]

This might sound stupid, but make sure the vacuum check valve underneath the fuel pressure regulator isn't on backwards.
S.

 

[IrvJr]

Mine did the same thing. But the door must've been stuck because now its working. It takes a second after you turn on the vent but the door opens hard with slight bam. I trouble shot the problem through a manual and it said it was the door farthest the drivers side towards the top. Its not very easy to get to. But maybe if yours is stuck, you could hook up that vacuum tool ( cant remember the name offhand), maybe it would free it up.

Just a thought

Scott

 

[PRSRIZD_V6]

Originally posted by Snorman
This might sound stupid, but make sure the vacuum check valve underneath the fuel pressure regulator isn't on backwards.
S.

If that check valve is shot then the chances are that the gizmo that actuates the valve under the dash is blown out from boost. Hopefully not as they are a pain to change.

 

[tc86gn]

disconnect the vacuum line under the hood that goes to the accesories. Connect a hand held vacuum pump and check it out. You may even be able to hear it leak or you will see if it holds vacuum to see if maybe a door is stuck. Just an idea. Mine did the same thing and when I hooked up the vacuum pump and pulled about 20 in. of vacuum, it came loose and has been fine ever since.

 

[kevinw]

Thanks guys for the tips,i'll try your suggestions in the next day or two and go from there.

 

[drew sharpe]

it might be the under dash cable linkage is broke and stuck on defrost and floor thats whats wrong with mine

 

[salvageV6]

Perhaps you knocked the vacuum line off the Bi-Directional lower motor vacuum motor or else the hose off the Upper Mode Vacuum Motor?

With no vacuum present air will pass out the defroster.

Probably related to the heater core install and a simple problem.

Either that or the bellows and doors are jammed also related to the heater core install.

I'd guess the upper mode vacuum motor behind the Inst. Panel on the RH side of the A/C plenum.

Blue hose. The dual mode motor has red and yellow hoses.

Make sure they are all attached at both ends.