95 grand am climate control problems

[t/a 6.6]

I am working on my buddy's 95 grand am. The air control nob is broken. It will turn very loosely. It does not do anything. The setting is stuck on defrost. He has taken off the nob several times and looked at it, but can't seem to get it to free up. I am just looking for some pointers, so i have an idea of what to expect before i head over there.

[3100]

from what I understood is that his plastic part of the knob (the half circle part that goes on the top of the metal lever is broken) so until he gets new plastic knob from junk yard why can't he use pliers instead of knob and set it to where he wants? But you said that he took the plastic knob off several times and looked at it so I am not sure if I understood your question since there is not much think about.

Originally Posted by 3100

from what I understood is that his plastic part of the knob (the half circle part that goes on the top of the metal lever is broken) so until he gets new plastic knob from junk yard why can't he use pliers instead of knob and set it to where he wants? But you said that he took the plastic knob off several times and looked at it so I am not sure if I understood your question since there is not much think about.

since there is not much to think about.

[3100]

Also make sure that all the vacuum lines are connected to the HVAC controller because if some of them are broken his setting will be set to blow air only at the windshield because that is the emergency mode so you at least can see where you are driving. And even if his knob was ok, he still would't be able to change anything untill vacuum lines are fixed. Also check all the plastic skinny vacuum lines under the hood especially around the vacuum modulator area and make sure all their rubber "T" and "L" fittings are tight.

[xeroinfinity]

If the knob just spins and doesnt change the direction selector then that sounds like the head unit(switch) is broken. That would require a replacement.

[YasirDahham]

Hi Dear Folks
Kindly advise as per those colored vacuum lines coming out of the Climatic Control Console of my Pontiac Grand Am model 1995. I have 4 thin lines hanging down the drawer cabinet on the right side of the dashboard( dark blue, red, violet and pale green). The cool air coming out of the A/C freezer is so weak it hardly reaches my face while the temperature is not convincing ( 18.2 Celsius). Seems like the cooled air is dissipated in so many routes rather than being directed in one direction. The attached images show these parts as well as a thin black vacuum line close to the PCM and coming all the way from the engine compartment along with the main harness.

[Blue Bowtie]

You can determine which one of the hoses is the manifold vacuum source by starting the engine and checking each hose for constant vacuum.

Once that is established, the vacuum source hose can be connected to the supply port on the function selector control. Turning the control to each function should reveal which port on the control is for which function.

Then it is merely a matter of which colored hose performs whcih function by connecting the vacuum source to each hose in turn.

[Blue Bowtie]

There is some uniformity to the schemes used by GM.

Very often, the orange hose is used for control of the recirculation/fresh air damper.

Purple is commonly the vacuum source.

Gray / Off-white is often used for the defroster damper.

Black is frequently the lower outlet damper.

[YasirDahham]

Originally Posted by t/a 6.6

I am working on my buddy's 95 grand am. The air control nob is broken. It will turn very loosely. It does not do anything. The setting is stuck on defrost. He has taken off the nob several times and looked at it, but can't seem to get it to free up. I am just looking for some pointers, so i have an idea of what to expect before i head over there.

There is a thin spring steel bush that is located inside the cavity of the knob( all 3 knobs), sometimes it just quits the plastic knob and rests rather on the chamfered shaft, it could be shoved deep down that it loses contact with the knob and this is why it seems so loose doing nothing. Without that steel bush the knob works nothing, just turning around the shaft.

[YasirDahham]

Originally Posted by Blue Bowtie

There is some uniformity to the schemes used by GM.

Very often, the orange hose is used for control of the recirculation/fresh air damper.

Purple is commonly the vacuum source.

Gray / Off-white is often used for the defroster damper.

Black is frequently the lower outlet damper.

Thank you dear pal, I received a schematic diagram for the vacuum lines. Violet connects to the main vacuum line coming from the engine side along the main thick harness. Green & Blue hoses connect to the same actuator assembly marked with a Green label, Yellow & red hoses both connect to the same actuator assembly marked with a Yellow label. I have images for these parts. The orange connects to the Outside Air actuator, this actuator is over the space where the PCM is fixed.