HVAC box question

[96redsport]

The air now only comes from the face vents and won't select to the defrost or the floor vents.... The HVAC controls are a few years old so I can't see it being that. Is this a problem of the mixer actuator and how hard is it to replace? Is there only 1 actuator or a few of them? Never messed with this fix before so please excuse the noobness of the question... LOL

 

[geltstavern]

I feel your pain, I'm looking at a similar problem in my 97 yukon. air only comes out the defroster. It could very well be just your mode actuator motor, it's located on the left hand side of the box under the dash. I picked up a new one from rockauto and it was cheap enough to try but after getting my fat ass under the dash I realized the actual door itself is flapping in the breeze so to speak. aint doin nothing but the actuator works.... I'm not looking forward to removing the dash, did it once before on my 96 suburban and invented some new curse words... good luck

 

[96redsport]

Yeah, I'm gonna try the motor first. I actually didn't realize until a few days ago that the motors were on the outside of the box so that should save me a lot of aggravation if it is a simple fix..

 

[AZ Tahoe]

I did remove my dash and replaced the whole box as mine was smashed in. If I remember correctly there is one above the 4x4 shift (if yours is also on the floor) one on the passanger side behind the glove box and another on the passanger side but behind the box against the fire wall.

 

[SunlitComet]

mode door motor left side of box above gas pedal linkage. temperature door motor in rear facing section of box blocked by dash support structure. recirc door motor and the forward side of box passenger side buried behind the blower.

 

[96redsport]

GM didn't make this easy did they??? LOL

 

[geltstavern]

Red, let us know how you make out, especially if you have to go deep and remove the dash... I'm planning on that task as soon as it warms up a bit, still have 6 inches of snow here in northern mass... damn global warming

 

[96redsport]

Yeah no crap Bill. Calling for more snow here in the next few days.... Hopefully it is just the actuator that went bad. That would be the simple fix.

 

[Monstar_est87]

Here u go fellas hope this helps... I put up pix in another thread sum where but couldn't find it... Ill keep looking...

 

[96redsport]

Thanks Monstar!

 

[SunlitComet]

mine is bigger and better.
Front HVAC Assembly

 

[Monstar_est87]

Took long enough...

 

[SunlitComet]

i have done enough already. thought by now i could ween you off a bit.

 

[Monstar_est87]

http://www.tahoeyukonforum.com/forum/showthread.php?t=25206

Check out this thread guys... The pictures I put up are on page 8...

 

[raptorforme93]

I just posted a shitload of pictures of the HVAC in this thread on page 2 if it helps

http://www.tahoeyukonforum.com/forum/showthread.php?t=48448&page=2

 

[96redsport]

Zach, that tear down looked like a PITA... Unfortunately I don't have a second vehicle so whatever I do to the Hoe has to be done in 2 days that I have off. Would love to do that and get everything in the HVAC running like new tho.... Nice work BTW..

 

[raptorforme93]

Yea it's doable in two days but it's a shitload of work and it was my first time so it was pretty slow going but I was able to clean it up a ton and replace a lot of old parts and seals. Here a the best pics I could find of all three of the actuator motors.

Heres the mode select motor which you seem to be having trouble with. Its sticking staight out the left side of the HVAC pointing into the steering column. You can probably see it with the whole dash installed and honestly it might be possible to replace it without removing the dash but it'd be close I think. (Its right behind the steering column support structure)

Pic of the very left side of the HVAC

Here is a pic of the temperature control door actuator in the middle of the HVAC facing back toward the cabin. Almost 100% sure this cant be removed without some removal of the dash, its behind a support structure.

Here are the ever elusive pics of the recirculator door actuator. These are the best I had to give you an idea of where it is it. It is actually the only motor that is uncovered and I'm pretty sure with a little wiggle work it can be replaced without removing anything else so it's not too bad despite being tucked way up under the dash.

---------- Post added at 03:00 PM ---------- Previous post was at 02:57 PM ----------

BTW to whoever thinks their AC is working at 100%, if your truck is as old as mine I can guarantee that it's not. Looking forward to seeing how much more efficient the new clean evaporator is during the hot ass summers down here in florida.

 

[SunlitComet]

sure mine is do for a cleaning to unfortunate when i removed my dash i did not do any gasket/seal work on the hvac so i am pretty sure i am loosing flow rate thru the upper ducts. just did not have the money to get new gasket stuff.