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I drive a GMC Sierra 2021 elevation

 

around 30,000 miles the AC would stop blowing. All the electronics are on, can change the temp, turn it on/off but no air at all is coming out. Brought it into the dealership they had it for 2 weeks, replaced the compressor and topped off the Freon. Within two days of getting it back it happened again. The issue is it happens on the weekend and it never fails Monday morning it is working again. Brought it back and they kept it for two days and couldn’t reproduce it so gave it back to me. Happened again the following weekend. Brought it back again, they kept it 3 days and couldn’t reproduce it. They told me they emailed GMC engineers who requested various readings, that they took and sent off and would call me when they heard back. AC worked fine the rest of the week but today, I stopped to get gas and when I turned it back on the air was again not blowing. I just turned the car on and it is working again. It is frustrating,  and the dealership basically told me unless I can bring it in when it’s not working there’s not much they can do as they can’t take the final readings requested by the engineers while it’s working. 
 

I think it’s freezing up because once it sits for a while (sometimes half an hour, sometimes all day) it will eventually start blowing again. When it is not blowing the heat doesn’t work either though, zero air is blowing out. It seems to happen after I’ve been driving a lot. The last two times it was after we drove to Baton Rouge and back to see family (about an hour each way), and the next day it would crap out. 


My warranty ends in a few thousand miles so I really want to get this resolved. 
 

Any help I’d appreciated. Not sure if me calling GMC would help, but every time I get in the truck or go anywhere I’m worried if it’ll be working when I turn the car on. It stays pretty hot down here until late October/November. 

thanks! 
 

Posted (edited)

Unfortunately I don't think there is a solution unless you can either figure out the issue yourself or get it to act up in front of the dealer.

 

I am (hopefully close to the end of) dealing with this type of problem with my CTS right now.  I started hearing a creaking noise that sounded like it was coming from the front suspension when turning left at low speed.  It only seemed to do it when the car was "cold" (like a first start in the morning).  Soon after that started, I noticed my steering wheel was no longer centered (if I centered the wheel I went left)...so I made an appointment and took it over, but BIG SURPRISE when I got in to drive it over, the wheel was centered and no noise.  OF COURSE!!  Dealer couldn't help.  Driving home from the dealer it was fine...but THE NEXT FREAKING DAY it was messed up again.  I called right away and made another appointment but same problem again.  EVERY G'DAMN TIME I WENT TO THE DEALER IT WAS FINE.  So I became determined to figure out a way to mess it up so I could show the dealer.  I drove around for over an hour just turning every which way at every speed and I finally figured out that if I spun the wheel all the way to left-lock position it would return off center.  AH HA!!! I drove right over to the dealer, left the car running and ran into the writer and said "come take a look at this!!!".  He said it probably needs a new steering column, but it's going in on Wednesday.

 

So basically as soon as you have the problem you need to get to a dealer and have it documented.  I know that's a lot easier said than done but unfortunately its what we are stuck with with these high tech machines we demand.

Edited by The Raven
Posted
On 10/1/2023 at 12:06 PM, jhobby024 said:

I drive a GMC Sierra 2021 elevation

 

around 30,000 miles the AC would stop blowing. All the electronics are on, can change the temp, turn it on/off but no air at all is coming out. Brought it into the dealership they had it for 2 weeks, replaced the compressor and topped off the Freon. Within two days of getting it back it happened again. The issue is it happens on the weekend and it never fails Monday morning it is working again. Brought it back and they kept it for two days and couldn’t reproduce it so gave it back to me. Happened again the following weekend. Brought it back again, they kept it 3 days and couldn’t reproduce it. They told me they emailed GMC engineers who requested various readings, that they took and sent off and would call me when they heard back. AC worked fine the rest of the week but today, I stopped to get gas and when I turned it back on the air was again not blowing. I just turned the car on and it is working again. It is frustrating,  and the dealership basically told me unless I can bring it in when it’s not working there’s not much they can do as they can’t take the final readings requested by the engineers while it’s working. 
 

I think it’s freezing up because once it sits for a while (sometimes half an hour, sometimes all day) it will eventually start blowing again. When it is not blowing the heat doesn’t work either though, zero air is blowing out. It seems to happen after I’ve been driving a lot. The last two times it was after we drove to Baton Rouge and back to see family (about an hour each way), and the next day it would crap out. 


My warranty ends in a few thousand miles so I really want to get this resolved. 
 

Any help I’d appreciated. Not sure if me calling GMC would help, but every time I get in the truck or go anywhere I’m worried if it’ll be working when I turn the car on. It stays pretty hot down here until late October/November. 

thanks! 
 

This is certainly not what we like to hear, jhobby024.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2021 GMC Sierra's A/C working intermittently. To do so, please send an email to [email protected] with ATTN: jhobby024/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s Privacy Policy, please visit https://www.gm.com/privacy-statement.html. The information you provide may be monitored and recorded and is subject to the GM Privacy Statement.
 
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