Strange noise from AC

[tammy0182]

Hello Everyone!
New forum member here, I own a 2009 Genesis 4.6. I have had the car for about a year now and I absolutely love it.
Today is the first day I have used the AC on full blast since last summer, and I don't remember this noise, but I could have had the radio on etc... I bought it at the end of summer beginning of fall.....
Anyway, when I switch on the cars AC and have the fan on full blast and the recycle air OFF it makes this really low pitched buzz sound almost hard to hear but I hear it. Husband is out of town, and I am taking it on a 300 mile trip tomorrow for the weekend with my 3 and 5 year old. If I switch the AC back to using recycled cabin air, the sound goes away to a point where anything I am hearing I think it may just be in my head.
I'm not a total car noob, I was raised by a mechanic and helped my fair share under the hood, so my concern is compressor, but not so much as to the recycled air is what seems to allow the noise.
Any thoughts?? Do you all experience a buzz too this way? (ha)
When I lower fan speed to a little over mid way the sound is gone. I also popped the hood and listened while I had the noise inside the car going, and could not hear anything. So maybe something inside the dash?
Sorry for the ramble, and thanks for the help!

 

[Gunkk]

Check the outside intake under the wipers for debris and clean as needed. keep it on recirc or half speed during your trip. when you get home pull the cabin air filter and check for loose bits that might be flapping about when on full fan.

 

[tammy0182]

Thanks for the reply Gunkk, I pulled the in cabin filter, couldn't see anything debris wise, also nothing near the intakes under the wipers. I'm wondering if something didn't get into the fan cage when the dealer did an oil change and filter change last week. The sound goes away when the fan is off, so I know it's nothing major. (At least I hope not!)

 

[landtuna]

Tammy,

I can't comment on the buzz but I noticed something else in your post you might not know. Over the wintertime in most of the USA it is too cold to use the A/C but the system still needs to run a little bit once in awhile to keep the seals moistened and the belts limbered up. It doesn't need to run long but should be run at least once per month.

Having said all that I am unsure if the Genny's heater/defroster also uses the A/C to keep the windows clear. If so, and you do use the defrost over the winter, then forget my suggestion.

 

[DRS]

Hello Everyone!
New forum member here, I own a 2009 Genesis 4.6. I have had the car for about a year now and I absolutely love it.
Today is the first day I have used the AC on full blast since last summer, and I don't remember this noise, but I could have had the radio on etc... I bought it at the end of summer beginning of fall.....
Anyway, when I switch on the cars AC and have the fan on full blast and the recycle air OFF it makes this really low pitched buzz sound almost hard to hear but I hear it. Husband is out of town, and I am taking it on a 300 mile trip tomorrow for the weekend with my 3 and 5 year old. If I switch the AC back to using recycled cabin air, the sound goes away to a point where anything I am hearing I think it may just be in my head.
I'm not a total car noob, I was raised by a mechanic and helped my fair share under the hood, so my concern is compressor, but not so much as to the recycled air is what seems to allow the noise.
Any thoughts?? Do you all experience a buzz too this way? (ha)
When I lower fan speed to a little over mid way the sound is gone. I also popped the hood and listened while I had the noise inside the car going, and could not hear anything. So maybe something inside the dash?
Sorry for the ramble, and thanks for the help!

Good suggestions above.. Which looks like you have checked out already.. What I am about to suggest is not likely the issue, but one item in a checklist you are going through. If you have a auto stethoscope with a probe, might try poking around touching areas to see if you can trace the source. Also touch the probe on the fan bearings. In past GM products (same for others too, not picking on GM) I had fan bearings that were a bit noisy, noise be masked in recirculating mode. Eventually replace the fan motors.

If the air filter is brand new, and noise started after that, you already know what to do to test.. If older, replace.. Did you take the filter out and run the AC for a time to see if the noise goes away?

Checking the entire HVAC system for some lodged tree seeds is a good idea. Since the spring is good timing for those to be dropping like leaves in the fall. They might be able to get through the intake.. Not sure.. Your thought of seeing if there is a cage that has something lodged is sound. Again, maybe the probe could help speed resolution.
,
i am sure you have determined the risk factors for your trip and concluded the noise is more of an annoyance than something else. If not found in time, Not likely something that will catch the car on fire while you drive on trip.

 

[craigt]

Sounds like a Dr. Phil episode.