Climate Control Troubleshooting

[Tinyface]

I'm trying to get my Ac working on my 1986 El Camino, I've traced the issue down to the control part of it (the part that you change to get vents defrost hot/cold air ect.).
I'm getting:

• A sucking sound on the right side with the wheel the changes where the vacuum goes
• Defrost is the only setting that's ever on even though other setting are used
• I do get some heat on the floor when driving with the ac on (the ac does blow cold when it needs a few minutes, old car and all that).
• A little bit of air flow when I hold my hand under the thermostat when I had it out last night

So my question is: what should I be checking to pin point the issue? I'm trying to replace as little as I can since the outside of the control is in pretty good shape. And also any advice anyone would like to give would be nice I'm really new to working on cars.

Thanks in advance.

 

[383_StealthRam]

I highly recommend you follow the diagrams, troubleshooting hints and system operation information from the following post.

Post in thread 'Airflow thru vents'

Aug 30, 2024

Have a look at the following post, assuming your blower motor is working fine (electrically) at all the speeds through the resistors, and the high blower relay, then you should go through the vacuum and air flow troubleshooting steps to determine what might be wrong.

Note, there's also the possibility that you have a lot of build up dirt on the the heater core, and/or evaporator core that is hindering air flow from blower motor from getting to the inside HVAC box. Also, you could have a lot of air leaking from dried out or missing foam seals around the plastic ductwork behind the dash...

• 383_StealthRam

• 

 

[BlairC_789]

The leaking is probably from the black maize like disc. You can find them in the junkyard in alot of gm vehicles in various years. Or it needs a bit more pressure applied to it to make it seal better

 

[Tinyface]

Thanks guys I saw this at work and ordered the replacement part, I'll go do the work a little before I start working on replace the sound system

 

[Tinyface]

Late update for anyone who finds this later, I got everything working.
This is what I did;

• I took out the climate control (this video is pretty helpful and I'd take out the radio as well since it gives you more space)
• Promptly broke the plastic clip that hold everything together (it's fine we get a new one with the part we're buying)
• Washed the little rubber maze dude with warm water and hand soap, and dried it with a hair dryer on low (don't know if this help it's something I did after I didn't get it working, along with bending the little star-ish shaped metal piece a little more, and snugging everything down a little more)
• Put on the new clip and the piece of spring metal that came with this part from Amazon. I'll caveat that you need to bend the little piece of metal a little more that probably.
• Grabbed some pliers and snugged down the clips that that hold the thing that holds all the vacuum lines to the rubber part (again don't know if this helped, I did it after it didn't work the first time)
• I put everything back together tested it out, and the trap door in the upper right hand part behind the glove box went up so I'm calling that working, might have some other issues, but I'll figure it out later

 

[Sweet_Johnny]

Late update for anyone who finds this later, I got everything working.
This is what I did;

• I took out the climate control (this video is pretty helpful and I'd take out the radio as well since it gives you more space)
• Promptly broke the plastic clip that hold everything together (it's fine we get a new one with the part we're buying)
• Washed the little rubber maze dude with warm water and hand soap, and dried it with a hair dryer on low (don't know if this help it's something I did after I didn't get it working, along with bending the little star-ish shaped metal piece a little more, and snugging everything down a little more)
• Put on the new clip and the piece of spring metal that came with this part from Amazon. I'll caveat that you need to bend the little piece of metal a little more that probably.
• Grabbed some pliers and snugged down the clips that that hold the thing that holds all the vacuum lines to the rubber part (again don't know if this helped, I did it after it didn't work the first time)
• I put everything back together tested it out, and the trap door in the upper right hand part behind the glove box went up so I'm calling that working, might have some other issues, but I'll figure it out later

Awesome! I still need to fix this on my Cutlass and appreciate the update and tips.

 

[69hurstolds]

Just a tip: When reassembling the maze disc(s) on these HVAC heads, it doesn't hurt to smear them with a LIGHT film of silicone lubricant. Not globbed on there, but just a film. If you hadn't noticed, there's a lot of places where it's used in that little HVAC head. You never think about how many times those knobs/switches are manipulated throughout the car's life.