2016 GMC yukon denali A/C not cold enough

[Brent Lanphier]

I just got my 2016 yukon denali and am very happy with is but not so much the A/C it only blows out 50 degrees witch in south texas at 95 degrees short trips around town (10 Min or so) 50 is not cold enough to cool of the car, I have had a lot of cars in my 65 years and in my experience anywhere from 38 to 40 is a more normal temp for the A/C system to work, the dealer say's they can't figure it out Maybe it's a computer problem nothing they can do about it, not a answer was looking for (80.000 for a car and nothing they can do about it) I really need your help.

[dfelicia]

Dealer confirms it's an issue? Like you went in the lot and measured another Denali's temp? If so, drive to another dealer and also call GM to complain. "Nothing thy can do" is BS if they agree it's not working right. Now, "you're expectations are off, we measured three more and all put out 50 degrees" would be a different ball of wax.

 

We're in a major heat wave up here in CT. My 2016 Yukon XL (not Denali - so 5.3) cools off OK. Not as well as my pickup truck did, but there's a helluva lot more cabin to cool. The air blowing out feels as cool as any other car I've had.

[66deadhead]

It's possible it could be slightly low on refrigerant charge from the factory, Or a faulty expansion valve or sensor. Or a combination of things. Try cranking it down to low and turn the cabin selector switch to recirc if you haven't already. From what I have read recirc will cool the cabin down quicker as it shuts off the outside air coming in and allows it to cool down quicker. I think When you use the remote start feature and the system is set to automatic that's how it operates thru the computer till the cabin cools down. If none of that seems to work, I would be taking it back to the dealer and demand they do a more thorough inspection. It gets hot and humid as hell here in the summer in the mid Atlantic. A/C in the summer here is a must and I wouldn't be going without it.

[The Zip]

If it wasn't getting cool at all would be the problem, I had to replace a faulty AC sensor cause that was my situation. But the dealer is correct, I have been driving my truck for 30 months and this is a standard operating condition on the fullsize SUV for the AC not to get ice cold.

[Jsdirt]

That's the best 134a can do. Thank the government for that one. If it was an r12 system, it would be blowing mid 30's on high at 100° ambient. Lots of variables too - an r12 system with too much oil will cool worse than a properly designed and serviced 134a system.

 

Just happened to do a performance test of my '07 yesterday - was blowing 45° out the center vent, parked & idling, fan on high, inside air (recirculate), at 90° ambient, 45% humidity. Switching to outside air raised the temp to 50°. About as good as that system is going to get.

 

I gave it a shot in the arm in '13, just because it had been 6 years. System seemed to work fine - blew 55° rolling down the road. After I added some refrigerant, it cooled better than the day it left the showroom floor. Right from the factory it was a touch on the low side. Not surprised. Blows low 40's when moving.

[MikeNH]

That's the best 134a can do. Thank the government for that one. If it was an r12 system, it would be blowing mid 30's on high at 100° ambient. Lots of variables too - an r12 system with too much oil will cool worse than a properly designed and serviced 134a system.

 

Just happened to do a performance test of my '07 yesterday - was blowing 45° out the center vent, parked & idling, fan on high, inside air (recirculate), at 90° ambient, 45% humidity. Switching to outside air raised the temp to 50°. About as good as that system is going to get.

 

I gave it a shot in the arm in '13, just because it had been 6 years. System seemed to work fine - blew 55° rolling down the road. After I added some refrigerant, it cooled better than the day it left the showroom floor. Right from the factory it was a touch on the low side. Not surprised. Blows low 40's when moving.

 

 

 

It may not be 134a anymore. My Jeep uses R-1234yf. I'm happy with how it cools but the Jeep has an exceptionally powerful HVAC system. The low fan speed is like high on some vehicles I've driven.

[Jsdirt]

I forgot about that - starting to see that more and more out there. Stuff is pricey too. I don't know a thing about it - how it behaves, or what the pressures are like.

 

I remember asking on the new model forum what they had for refrigerant - If I remember right someone replied that had a '15, & said it still uses 134a. I'll try and find my post.

 

Couldn't find my post, but I found this - pretty much answers my question: http://www.gm-trucks.com/forums/topic/185393-r-1234yf-refrigerant-rollout-coming-in-2017-model-year/?hl=refrigerant

[MikeNH]

the yf stuff is also massively flammable. But it'll protect the environment as a burn alive if I ever wreck the Jeep.

[Jsdirt]

LOL - it's pretty clear they put the "environment" on a bar high above human life (any life that isn't theirs, their families, or their cohorts).

 

I just spent the last hour reading about it, and watching Youtube vids. It's clear there is ZERO benefit to using it, except that it has a "lower global warming potential".

 

I smell another scam, just like in 1993. Guess I'd better start stockpiling 134a ...

[Brent Lanphier]

They have pulled all the freon out of the system and pulled a vacuum on my yukon and checked everything they can check and we can only get at the lowest running down the highway at 50 degrees witch if your running down the highway all day is fine but just for short trips around its just not cold enough to feel comfortable or at lest a little cool and with the front A/C on low and the rear A/C on low and it can do no better than that something is wrong, I have a 2002 ford supper cab and that A/C will blow out 35 degrees and its 134a it will freeze you out I was just thinking when you spend 80.000 on a car you could get cold air, I have no idea why they have the controls to adjust the temp when you have to leave it on the coldest setting just for it to work a little.

[Jsdirt]

Might have an overcharge of oil, or trash between the condenser and radiator, or condenser loaded with bugs, dead fan clutch or e-fan ... list goes on.

 

134a systems using 134a do cool very well (most of them, anyway), but they'd cool even better on r12. One of the main things you had to do on conversions back in the 90's was to increase the condenser size (if at all possible) to the largest condenser you could fit. That right there shows the decreased efficiency.

 

Leave it to the government to take something that worked perfectly and ruin it, by forcing automakers to use a second-best refrigerant.

[Brent Lanphier]

I was even thinking it could be a computer problem not letting the compressor run long enough and it is a brand new car not even 500 miles on it.

[Jsdirt]

Yeah, that's a distinct possibility too. In fact, when I'm in doubt, I blame the electronics every time - that usually is to blame for a problem in a new vehicle.

[Brent Lanphier]

I wish there was someone on here that tell me something about how or if it is programed just to get 50 degrees and if so could GM fix that.

[Jsdirt]

I've never heard of a unit programmed to a certain vent temperature.

 

Normally they rely on a sensor in the cabin that tells the computer that it's getting too warm in there, and then it engages the clutch, and speeds up the fan accordingly.