Complete Catostrophic A/C Failure - A Please Help Thread

[Wooty]

Firstly, have a stock '06 Z71 Tahoe with around 180k miles on it, and it's been having issues on and off for several years now until recently.

Firstly, when my grandfather owned it, it would, maybe once every six-twelve months decide to turn on the heater. The only way to remedy would be to pull over and turn off the car and back on again.

As of several months ago, the heat issue became more frequent and eventually the A/C just wouldn't get cold after reloading with freon. Then one day my A/C would not shut off... Leading me to pull the relay out to cut the A/C completely off. I would pull and replace the relay when needed as outside air is better than nothing (drive down I-10 gulf coast during summer A TON).

Last week, as I pulled in my driveway my A/C compressor started smoking and suffice to say the A/C belt is off and relay is pulled.

I am not a big gear head but I work on custom electronic projects and have replaced transmissions and done some other auto work so I'm not intimidated but don't know where I would need to start on restoring my complete A/C system, or if it would be worth it.

I'm told theres a mysterious control module thats expensive that needs to be changed, I'm gonna have to rip out my dash and replace a ton of components. So my real question is...

Too long; didn't read: What information or resources are there for me to replace my A/C system, and what can I probably avoid replacing? What will it probably cost doing my own labor? Thanks again, and apologies for the long conveluted post.

 

[Doubeleive]

if your lucky it's just a blend door actuator and a a/c compressor (compressor,Freon & labor), some people say to replace a bunch of things related to the a/c compressor when it goes out but unless you have evidence of metal in the tubes then I wouldn't worry about it, sounds like it just froze up. as far as tearing a bunch of things out of the dash not likely unless it just happens to be that one actuator that is deep inside, the other two are easily accessed from under the dash passenger side kick panel that sits under the glove box.

 

[SnowDrifter]

What refrigerant were you using?
Why did you keep adding?
What were your pressures?
How much was in the system?
Where was your leak?
Were you losing oil?
Were you adding oil?
Did the stuff you were using have any stop leak?

 

[Big Mama]

Might be time for a shop manual. Lots of them on line it you can find a Haynes at Advanced or Auto Zone

 

[treehan77]

The randomly turning heat instead of a/c is almost always one of the blend doors. Cheap and easy to replace. I'd do that, then set about seeing if you need a new compressor or what.

 

[S33k3r]

Wow! This sounds like the same symptoms I'm experiencing in my Suburban. Mine are just like the beginning of your symptoms, in terms of heat kicking on when the AC should be blowing. Turning off the engine then restarting temporarily solves the issue, until I hit a significant bump. My mechanic diagnosed it as a bad blend door (if I remember correctly). In my case, the door that controls recirculating versus fresh air is stuck open to fresh air (yay). He also indicated my compressor is weak, and that the accumulator needs to be replaced (I *think* it is the accumulator, I can't remember; I am sure about the compressor). Basically, he isn't sure if a weak compressor caused the accumulator to go, or a bad accumulator caused the compressor to go... Anyway, he wants about $2k, including parts, to fix everything.

Though he is likely not the most inexpensive mechanic around, he charges reasonably, and is honest. And his work has never had to be redone. So I'll be partaking of his services this next spring.

That said, I'll be watching this thread with interest.

 

[2011SSVHOE]

Might be time for a shop manual. Lots of them on line it you can find a Haynes at Advanced or Auto Zone

also time to get a Tech2 scanner , that will get to the root problem. but it sounds like you are gonna need a compressor to start with. or it might be cheaper to move to Alaska where they don't need AC. I know i'm a smart ass. sorry!

A/C work is fairly easy, you can get the tools online or at Harbor Freight and a book and do it your self. I got a Compressor and all the stuff a couple years ago off of Ebay and still purchasing the tools I came out cheaper than taking it to a shop, and I still own the tools. ( gage set and vacume pump)

Good luck !