When I drive on long trips my a/c freezes up and stops blowing cold air. Seems like the evaporator is icing up. Took to dealer and could not replicate. I was driving home the other day after about 3.5 hours it did it again. I took it into the closest dealership and they agreed but couldn't verify the problem because they would have to go through a checklist of things before tearing the dash apart to access the evaporator. I was still about 5 hours from getting home and couldn't wait an undetermined amount of time to diagnose . This is so annoying . Anyone else come across this issue? Is there anything I can do to prevent it from icing over?
A/C problems??
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Usually A/C and Refrigeration systems use a metering valve to control the flow of refrigerant to the evaporator. The valve’s output is supposed to change based on the superheat (excess) heat leaving the evaporator. If it’s starting to ice up, the valve should be throttling the Freon until it thaws out.
This should not be happening and isn’t normal.
This should not be happening and isn’t normal.
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We were pulling the bass boat with our Colorado two weeks ago and had the first problem with our a/c. It started blowing really hot air out with the max a/c on. I turned the heat on and let it blow on high with the defrost as well for about 5 minutes and tried to turn the a/c back on...still blew hot! We got home and unhooked the boat and parked the truck. Within less than a half an hour there was a massive puddle under the truck where the condenser and cooling had came out of vaporlock. Since then there have been a couple of times it's blown warm and not very cold at all but I know that the dealership will do the exact same thing with me that they are doing with you because they can't just go off of hearsay on diagnosis of a vehicle, they have to have actual symptoms while it is in the shop. I don't know what to do about it but I will be taking mine in sooner than later as well!!
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I am having a similar problem. While on a very long road trip, about 8 hours in, the AC stopped blowing cold. I turned off the AC button and cycled it back on and it started blowing nice and cold again for about 20 minutes. This behavior continued for the rest of the trip, which was another 2 hours. I parked it for about an hour and took it for another drive, about 45 minutes, and there was no problem. The truck almost exclusively is used for sporadic long roads trips. The truck just hit 11,000 miles and has not previously exhibited this problem. I will be taking it in for its second oil change soon and will ask them to take a look but I suspect I will get the same response as the rest of you.
I've noticed that when I'm just starting to drive or taking short trips if I'm at a stop light, the A/C stops blowing cold. It's cool, but not nearly cold enough to cool down the cab. I plan to take it in to see if I can get them to replicate the issue. I'm planning a long trip this summer and if the A/C fails to cool the cab properly (it's small in there compared to my MDX which blows ice cold and cools down the passengers way in the back in no time), I'm going to be really annoyed.
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Is it possible that Freon is no longer used (or was changed) so the a/c isn’t as cold as it used to be in older vehicles?
I feel like I heard a rumor that Freon was going bye-bye
I felt like r134 never got as cold as r12 did Maybe this is a similar change
I feel like I heard a rumor that Freon was going bye-bye
I felt like r134 never got as cold as r12 did Maybe this is a similar change
It blows super cold if I have it at like 68 or something way below outside temp. The issue is when I hard brake or hard stop completely. All of a sudden it just blows warm. Dealer said they need the truck all day to see if they can replicate. I just got my first free oil change, only did 7500 miles in a year. The appointment was late in the day so they didn't have time. Next time I'll have them check since summer is over. Plenty of time on warranty.
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Best reply.
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Are you in recirculate mode or let fresh air in mode. On a long trip I switch to fresh mode periodically to let in fresh air.
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What temperature do you set the AC at. I set mine at 72 degrees. I think I once experienced something similar to you but noticed temperature set to LO. Changed to 72 & never had problem again . Who knows, sounds to me like made in China
electronic sensors that don’t work correctly.
I read The blowers in the HVAC come on slowly by design by GM to make blower motor last longer. My wife bought a fancy$$ German vacuum cleaner that does same thing.
I recently picked up my 2016 Colorado duramax yesterday from the dealership after taking it up there 3 times and showing them a video with me using a laser thermometer (or whatever its called) to show that my A/C would blow all the way up to 90+ degrees. First they said it was just low on Freon, 2nd they said they were attempting to locate a slow leak then after a few words being exchanged with them they finally found the clutch in the A/C Compressor had shorted out as well as the High Pressure Switch. So needless to say 500 dollars later my A/C problem is fixed with a new compressor and switch. Hope this helps
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Thank you for reaching out. We certainly understand how air conditioning concerns can be frustrating. If you'd like an extra layer of assistance while working with your Chevrolet dealer, please contact us by going to https://www.chevrolet.com/contact/chat. We are always happy to help.
Amanda M.
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We apologize for any dissatisfaction you're experiencing. If you'd like additional assistance while working with the dealership, when your air conditioning concern is present, we are more than willing to help. For us to do so, please reach out by going to https://www.chevrolet.com/contact/chat. We look forward to hearing from you soon.
Amanda M.
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357 Posts
Well, another long trip and more air conditioning problems. Same problem as the previous long trips. The AC blows fine for hours and then stops and blows only lightly cool. I turn it off for about 10 minutes and it blows cold again for another 10 minutes. If I shut it off for 20 to 30 minutes it blows cold again. Sometimes, the problem stays away and others it returns. As it only occurs after driving for hours, it is impossible to replicate when at the dealer. I have heard of this issue from others. I have to believe GM knows about it and there must be a fix. Would GM please send out a TSB and advise the dealers how to fix this!!
My A/C works at first when I start the vehicle. 2016 Duramax (47000 miles). Seems normal but then after driving awhile (5 minutes or so) it quits producing cold air. It's pretty much done after that, however, it will occasionally kick in and work for only seconds then warm again. Had it recharged and also installed a new relay of some sort and no real improvement. It would seem tough to diagnose? I'm now out of warranty so as one person commented" they (the dealer) finally found the clutch in the A/C Compressor had shorted out as well as the High Pressure Switch. So needless to say 500 dollars later my A/C problem is fixed with a new compressor and switch". In my case, perhaps this is the best explanation, except it seems it would only be caused by the switch. But one other thing is I can visually see that the a/c clutch disengages so perhaps there is some sort of a switch or sensor contributing, because, if the clutch is engaged it pumps cold air.
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