sometimes my air controls dont work

[cam98aro]

like i will put it on defrost only, and it will come out of hte middle vents, defrost/legs, and it will still come out the middle vents, legs only, it still comes out the middle vents.

it kinda gets annoying... anyone know how to fix it?

like, the flap inside is moving, because i can hear it (sometimes) and you can hear the vacuum sound.

[BBlandin87]

Re: sometimes my air controls dont work

I'm not sure of the differences in how the A/C and Heating are setup on different year models, but I have a 1995 3.4L V6.

This is how my system works in regard to your problem:

The temperature control flap is manually controlled by a cable through the middle knob on the climate control panel.

The first knob sets the fan speed and is nothing but electrical.

The last knob has a main vacuum line running to the back of it and several other colored lines....the main line should be black.....each colored line runs to an actuator, which either controls the floorboard flap, the defrost, the face vents, the combination of both face and floorboard,etc....I believe one actuator has two colored lines running to it, and I think it is the one that controls the combination of face and floorboard flow......anyhow, when you turn this knob, the vacuum routes to a colored line to actuate the selected flap.

My best guess is that you have a leak with the black vacuum line, and I bet it is leaking or either losing vacuum through a check valve located near the ECU under your hood. If you look near your ECU, you should see a black cylindrical check valve with three black plastic lines attached to it.....It should be on either side of your evaporator case.

I'd check that check valve first. You can also check for the connections of the colored vacuum lines by taking out your glove box. You should see a main connection for the colored vacuum lines sitting against your heater core cover. Although, I don't think this is the problem....They are attached together firmly.

Of course, you did say that you hear a vacuum noise when you turn the temperature control knob......so I don't think we have the same setup.....but just in case, I hope this helps!

[cam98aro]

Re: sometimes my air controls dont work

I'm not sure of the differences in how the A/C and Heating are setup on different year models, but I have a 1995 3.4L V6.

This is how my system works in regard to your problem:

The temperature control flap is manually controlled by a cable through the middle knob on the climate control panel.

The first knob sets the fan speed and is nothing but electrical.

The last knob has a main vacuum line running to the back of it and several other colored lines....the main line should be black.....each colored line runs to an actuator, which either controls the floorboard flap, the defrost, the face vents, the combination of both face and floorboard,etc....I believe one actuator has two colored lines running to it, and I think it is the one that controls the combination of face and floorboard flow......anyhow, when you turn this knob, the vacuum routes to a colored line to actuate the selected flap.

My best guess is that you have a leak with the black vacuum line, and I bet it is leaking or either losing vacuum through a check valve located near the ECU under your hood. If you look near your ECU, you should see a black cylindrical check valve with three black plastic lines attached to it.....It should be on either side of your evaporator case.

I'd check that check valve first. You can also check for the connections of the colored vacuum lines by taking out your glove box. You should see a main connection for the colored vacuum lines sitting against your heater core cover. Although, I don't think this is the problem....They are attached together firmly.

Of course, you did say that you hear a vacuum noise when you turn the temperature control knob......so I don't think we have the same setup.....but just in case, I hope this helps!

thanks, i will check it out. I can hear the vacuum in acually all of the cars i have.. so im not sure about that, but i will check everything else out