17 Denali AC / Fan noise

[GMC_nolonger]

My first post never addressed one of the issues I'm having (I thought it was done) so I started a new thread...

2017 Denali XL ~10k mi

Whenever the climate control is on, AC or not (I think the AC runs even on heat, etc.) There is a noise that sounds like a old car when the AC clutch first starts and you hear it building pressure, except this is a constant noise that changes pitch with the engine RPM, when climate control is switched to off, it immediately goes away. Sound comes from the passenger foot area.

I first thought it was a bad fan or the ground was improper, something along those lines.

Took it to GMC dealer and they immediately replaced the "AC system" what I was told, turns out it was the compressor, and it made some sense to me that could be the cause. Didn't fix it. Took it back, they said they must of got a bad compressor, replaced it again. Didn't fix it, they knew it, told to bring it back when they get a new fan in. Replaced the fan, still didn't fix it but they gave it back and said "you should be good now".

Anyone had a noise like this, is this normal? I would think I was just hearing things except even the dealer spent a lot of money trying to fix it, I was assuming they would tell me they couldn't hear it, but at least they could and tried...Other than that the dealer/ service writer is horrible to deal with, and denied other issues that were obvious, so its a bit strange.

thanks!

 

[sickk23]

My AC makes a howling noise especially when you let off the pedal. It’s very annoying.

 

[GMC_nolonger]

My AC makes a howling noise especially when you let off the pedal. It’s very annoying.

hmm....I would say I hear it more when the rpm is going downward too...If I never heard the sound it probably wouldn't bother me but now it all I hear

 

[Tahoe14]

If you are having other issues that are not being addressed as you indicated along with this one then file a Lemon Law case and see how fast they want to fix your truck. You could also reach out to GM and have your case documented or try another Dealer.

 

[sickk23]

hmm....I would say I hear it more when the rpm is going downward too...If I never heard the sound it probably wouldn't bother me but now it all I hear

Does it come from behind the passenger side dash too? The sound I hear absolutely annoys me, especially if I’m riding shotgun and not driving.

 

[GMC_nolonger]

Does it come from behind the passenger side dash too? The sound I hear absolutely annoys me, especially if I’m riding shotgun and not driving.

Yes, it sounds like its at or near the firewall. I hear it a lot more in the passenger seat. What year is your rig?

 

[Tahoe14]

You may want to do a Google search as I saw a post on a chevy truck forum. The owner put dum-dum on the AC line at the firewall after several attempts to fix the issue at the Dealer.. May be worth a try.

 

[sickk23]

Yes, it sounds like its at or near the firewall. I hear it a lot more in the passenger seat. What year is your rig?

2018 Suburban Premier

 

[GMC_nolonger]

You may want to do a Google search as I saw a post on a chevy truck forum. The owner put dum-dum on the AC line at the firewall after several attempts to fix the issue at the Dealer.. May be worth a try.

Thanks, I searched and found that post, with a picture. I'll have to see if I can pinpoint the noise to that location and give it a try. Seems they were having the same issue with the truck, and dealer tried the same things to fix it but couldn't .... and then they fixed it with a little trip to home depot, kind of funny. thanks for the heads up

 

[Tahoe14]

Your welcome and I hope it is the fix you are looking for.

 

[bobsyouruncle]

Thanks, I searched and found that post, with a picture. I'll have to see if I can pinpoint the noise to that location and give it a try. Seems they were having the same issue with the truck, and dealer tried the same things to fix it but couldn't .... and then they fixed it with a little trip to home depot, kind of funny. thanks for the heads up

Could you post a link to that other forum post. I'm having no luck finding it myself. Thanks.

 

[sickk23]

Could you post a link to that other forum post. I'm having no luck finding it myself. Thanks.

You’re having this issue too?

 

[bobsyouruncle]

Yes. New 2018 Yukon Denali, just 2500km on the odometer.

This noise and another. The 2nd unusual noise sounds similar to that ringing you get when running your finger on a wine glass. That 2nd noise is related to the throttle position (ie: starting a hill climb) and might be a fuel pump issue. Found a tech bulletin P5395A that might be the cause. I haven't been to the dealer yet.. want to put a few km on the vehicle first to fully understand the "regular" sounds vs problems.

 

[Tahoe14]

Growling noise-dashboard pass side-2015/2016/2017/2018, try these exact words in your Google search.

 

[bobsyouruncle]

Thanks for the tips on finding that forum thread.


Everyone.. here is a link to the thread: https://www.gm-trucks.com/forums/topic/208687-growling-noise-dashboard-pass-side/

 

[bobsyouruncle]

This solution solved my noisy AC. To recap I have a 2018 Yukon Denali with just 3000km. Driving around town with the AC on, running low, resulted in a whine that changed along with the engine rpm's. It started immediately when I got the vehicle and was so annoying that I usually kept AC off and wasn't looking forward to the summer heat coming. I never brought this issue to the dealer yet as I wanted to get a few more km on the truck and go there with a potential list (vs one-off visits).

I used two bars of duct seal.. cutting off 1" pieces, flatting them out and wrapping sections of AC line where it passed through the firewall.. until most of all the metal lines were covered.

Did the wrapping this morning and made a few trips around town and the noise is gone. Very nice!

Hope this solution helps someone else.

 

[Jonathan82]

This solution solved my noisy AC. To recap I have a 2018 Yukon Denali with just 3000km. Driving around town with the AC on, running low, resulted in a whine that changed along with the engine rpm's. It started immediately when I got the vehicle and was so annoying that I usually kept AC off and wasn't looking forward to the summer heat coming. I never brought this issue to the dealer yet as I wanted to get a few more km on the truck and go there with a potential list (vs one-off visits).

I used two bars of duct seal.. cutting off 1" pieces, flatting them out and wrapping sections of AC line where it passed through the firewall.. until most of all the metal lines were covered.

Did the wrapping this morning and made a few trips around town and the noise is gone. Very nice!

Hope this solution helps someone else.

I bought a 2018 Tahoe in November and have been hearing a very annoying whining sound between 1200 and 1500 RPM. This is most annoying because I hover around these RPM's for 3 hours a day sitting in traffic. It does it in any gear as long as you're in that RPM range and it does it in park, neutral or driving. The sound seems to stay on the drivers side of the car. I took the truck back to the dealership twice and they don't know what it is. I test drove a new 2019 and it had the same problem. I'm assuming it's one of the pulleys or maybe what you experienced?