AC not blowing through vents?

ace · Oct 20, 2009

My AC does not blow through the vents that face the passengers, only through the footwells and defogger vents. What could be the issue? It's a 96 GT vert if that helps. Thanks

JeremyAlan · Oct 20, 2009

it does not blow through any mid-level vents? or it only blow in the driver side vents? that part confused me.

My old V6 had this problem. There was a broken vacuum line that ran across the engine bay. replaced it and she worked like a dream.

stanger · Oct 20, 2009

Check the resistor behind the glove box and make sure that all lines are connected properly. 5 min fix.

JeremyAlan · Oct 20, 2009

stanger said:
Check the resistor behind the glove box and make sure that all lines are connected properly. 5 min fix.

also- could vac lines come unplugged from the switch it self?

ace · Oct 22, 2009

The vents that face the occupants so I guess the midlevel vents. It can't be the resistor because the blower does work, its just that no matter what setting i put the right knob on for example vent or norm ac it always either blows through the defogger and/or the footwells. i checked the vacuum lines but none seem to be broken. Where does the line that goes into the firewall connect to? Thanks!

CC'S95GT · Oct 22, 2009

the vacuum manifold is located on the driver side and the line goes along the fw to the passenger side where it enters the passenger compartment. The line is very small

ace · Oct 23, 2009

Hm, I guess I wasn't looking at the right lines. I'll check in the morning

JeremyAlan · Oct 23, 2009

i'll try to get a pic too tomorrow.

i assume you own a GT?

ace · Oct 23, 2009

The only vac line I see is this one.

And it gets plugged into this canister.

And then the black line comes from the canister and there is vacuum all the way to here. None of the other color lines have vac though...

CC'S95GT · Oct 23, 2009

All of the colored lines are the ones that operate the vent doors.
So you DO have vacuum in the black one when the car is running? Correct? Can you put a guage on it to see how much vac you have?
If you do have vac then the next place to look would be the control panel

stanger · Oct 23, 2009

Awesome post DESERTCOX05! Now that's how you help someone. I'm going home to check mine now. I know that my heater box is broken, it was that way when I bought my car. When I turn the fan on it doesn't come on until it's on high and it only would blow under the passenger dash. Upon further investigation I noticed that the blower box was all busted up and I can see the heater core. It's not hooked up through the firewall and I don't know where the two lines coming through should go. In addition, I taped up the box as best as possible to at least get air moving across the windshield on cold mornings but that doesn't help since it's not heated at all. Can anyone tell me where the two heater core lines attach to in the engine bay? Also what is the best way to test the heater core for leaks, just add water? And last is it possible to replace the blower box without taking my dash apart?

ace · Oct 23, 2009

DESERTCOX05 said:
All of the colored lines are the ones that operate the vent doors.
So you DO have vacuum in the black one when the car is running? Correct? Can you put a guage on it to see how much vac you have?
If you do have vac then the next place to look would be the control panel

Yea the black one has vac and no sadly i don't have a vac gauge

CC'S95GT · Oct 23, 2009

stanger said:
Awesome post DESERTCOX05! Now that's how you help someone. I'm going home to check mine now. I know that my heater box is broken, it was that way when I bought my car. When I turn the fan on it doesn't come on until it's on high and it only would blow under the passenger dash. Upon further investigation I noticed that the blower box was all busted up and I can see the heater core. It's not hooked up through the firewall and I don't know where the two lines coming through should go. In addition, I taped up the box as best as possible to at least get air moving across the windshield on cold mornings but that doesn't help since it's not heated at all. Can anyone tell me where the two heater core lines attach to in the engine bay? Also what is the best way to test the heater core for leaks, just add water? And last is it possible to replace the blower box without taking my dash apart?

2 heater lines- what year and motor do you have?
testing the heater core- connect water hose to to 1 line and water should come out of the other
replaceing the heater core/ box- your going to have to nuke your dash. It's highly labor intensive if you have a dealer do it.

ace · Oct 24, 2009

Ok, so i remove the control panel bezel and I can see the flapper door. So when I put it on "vent" it tries to open but doesn't so i push it a bit and then it opens. Does this mean i don't have enough vacuum or what? Uh, I'm so close!