[ct0099]

I have researched this type of noise through the forums and found that this type is either inherent in the car, AC orifice or low on refrigerant. My noise is noticeable while driving highway speeds and definitely related to the AC for I can turn it on and off with the AC switch. Most noticeable while driving down the highway after just starting the car after work and driving home in the middle of the afternoon. Seems like after the interior cools down, the noise is less loud. Sometimes it feels like the AC is not putting out cool air all the times. It is not a constant loud noise but comes and fades as I drive. Can hear easily even with radio on.
Any others with this experience? Thanks.

 

[Mehran333]

I have researched this type of noise through the forums and found that this type is either inherent in the car, AC orifice or low on refrigerant. My noise is noticeable while driving highway speeds and definitely related to the AC for I can turn it on and off with the AC switch. Most noticeable while driving down the highway after just starting the car after work and driving home in the middle of the afternoon. Seems like after the interior cools down, the noise is less loud. Sometimes it feels like the AC is not putting out cool air all the times. It is not a constant loud noise but comes and fades as I drive. Can hear easily even with radio on.
Any others with this experience? Thanks.

Well the cool air at all times, how often does that happen? Could you explain if that is like one day it would be cool and another warm and then repeat, or has it been warmer recently? Please detail that information for our diagnostics team.

On the noise issue, the fading of the noise, when does it happen? When the A/C is on and you accelerate/decelerate, or when the A/C is off etc. etc.

Personally have not had this experience as my own A/C is having serious problems of its own and doesn't even turn on :lol: but more detailed information will help us help you, ct0099.

 

[The_Ghost]

ct, your probably best off taking it to a reputable dealer if your concerned about it. A/C issues are almost impossible to diagnose over a forum. They aren't as straight forward as a CEL code or something of that nature. Now as far as your comment about the a/c not cooling at times. Are those times when you've been sitting idle for more then 15+ seconds? If so, it's normal. The compressor is only turning at idle speed when you are sitting and not building as much pressure, thus the a/c tends to warm up a bit. Same is true if you call for a certain percentage of throttle. It shuts off the compressor momentarily to give the engine all of the power you are calling for, like a plane on takeoff....they shut off all uneccesary accessories.

 

[Seltzinator]

Mine makes a high pitch whine also, that kinda changes pitch like a slide whistle. Though mine is only noticeable when idling. I haven't worried about it.

 

[Mehran333]

Have either of y'all tried to idle the car in the garage/shade and closely listened to where this sound is actually coming from? Is it the compressor, the pressure system, or what general area?

 

[GMCustomerSvc]

ct0099,

I see that The_Ghost advised a dealership; if you do decide to go this route, please do keep us updated on your progress there. We're available if you feel you should need additional support.

Sarah (Assisting Erica)
GM Customer Care

 

[ct0099]

What I mean about the change in cooling is when I am driving home and the AC is on sometimes when I put my hand up to the air outlets it feels like the air is not as cool as other times and can be noticed inside the cabin, then it feels cooler again all as I am driving highway speed at a set speed and not changing rpms. The noise comes and goes as I am driving like this. As soon as I turn off the AC, the noise quits and vice verse. I am not talking about at idle but when driving down the highway. At idle it makes the normal AC noise which is no problem and cools well. Like Seltzinator describes, a high pitch whine that changes.

 

[Shadofax]

The noise is likely related to serpentine belt slip. With AC on, the drag will be more. How many miles on your vehicle? If these vehicles have a serpentine belt tensioner that is weakening due to miles, or an old belt, or a new one that is cheap, or something got on the belt, these could all cause an issue.

 

[ct0099]

The miles are 20K. Today coming home from work I turned on the AC and did not experience the noise all the way home- 18 miles of highway driving at 70-75. It was overcast and in the low to mid 70s. What I have noticed is that when the temp outside is hot and the interior is to, then is when I hear this noise. As the interior cools down or like today the outside air not hot, it appears to be quiet or at least not noticed. Go figure?? I turned the AC off several times to see if any change in noises and did not hear anything different.

 

[Shadofax]

The miles are 20K. Today coming home from work I turned on the AC and did not experience the noise all the way home- 18 miles of highway driving at 70-75. It was overcast and in the low to mid 70s. What I have noticed is that when the temp outside is hot and the interior is to, then is when I hear this noise. As the interior cools down or like today the outside air not hot, it appears to be quiet or at least not noticed. Go figure?? I turned the AC off several times to see if any change in noises and did not hear anything different.

Well, it's a matter of how hard your system has to work. The longer and harder the AC is asked to remain on during hot weather, the more the system is working, just like in your home AC. Course your home is not belt driven. I'd have to look and see what we have for tensioners, what belt tighness is recommended, and what belt is suggested. Have you checked your belt, does it feel firm and is there any liquids on it that shouldn't be there?

 

[jeff465]

On my coupe my noisy AC was fixed,TSB # 09-01-39-006 and part # is 89025005 (A/C thermal valve kit). The noise was coming through the vents and got louder with acceleration.

 

[ct0099]

Thanks to all for the input so far. jeff465- did you experience same type of noise as I am describing for your repair? Would low refrigerant be part of the equation? How does the thermal valve kit play a role?

 

[Spartan]

I mentioned this when I tood my RL into the dealer and they said there is a brace. They installed it under warranty and that vibration noise was gone afterward. The dealership is now owned by Ted Britt but I think it is called "Sterling Chevrolet" out of Sterling Virginia. The service manager (Chris) there and another tech came over from Fairfax Saturn and they know the kappas. i would call them to see if there is a part number they can get for you.

 

[jeff465]

Thanks to all for the input so far. jeff465- did you experience same type of noise as I am describing for your repair? Would low refrigerant be part of the equation? How does the thermal valve kit play a role?

The noise was a whurling whine sound that got louder as the RPMs went up with the AC on. They did evacuate the freon to install the kit. I think the kit comes with the brace that Spartan mentioned. The temp wasn't a problem with me, just the noise.

 

[ct0099]

jeff465 That sounds like my issue. I will check into this and thanks to all for the input. This is a great forum to get the right information about our wonderful cars. I'll have my service guy check that TSB number out.

 

[ct0099]

drove home today... temp outside was in upper 70s...when I got into the car, the interior temp wasn't that warm but turned the AC on anyway for the ride home...driving highway speed(67mph- wasn't in a hurry) did not hear the AC noise as I have described before. Some relationship between higher temps outside and amount of temp drop the interior requires.....

 

[bb_kaytor]

Mine makes a high pitch whine also, that kinda changes pitch like a slide whistle. Though mine is only noticeable when idling. I haven't worried about it.

Mine does that too, enough so that I tend to shut it off at stop lights due to embarrassment. It is fine at anything above an idle though.

 

[redcoats1976]

mine does it too,apparently im the only one that has noticed.if anyone says something about it at a stoplight im going to tell them its just the turbocharger...LOL

 

[MidniteBlues]

On my coupe my noisy AC was fixed,TSB # 09-01-39-006 and part # is 89025005 (A/C thermal valve kit). The noise was coming through the vents and got louder with acceleration.

I agree with this initial suggestion, found the same answer in the www for issues with other cars..:yesnod: It could also be called "expansion valve".

Thanks to all for the input so far. jeff465- did you experience same type of noise as I am describing for your repair? Would low refrigerant be part of the equation? How does the thermal valve kit play a role?

If and when they replace the valve, the refrigerant will be checked and or refilled as part of the job..(at additional costs of course).. I think the best to diagnose and repair however would be a GM dealer.. However, what bothers me a bit is that you are now stating that's "intermittent", intermittent problems are the most difficult to diagnose & fix no matter what the object is... What if you go have it checked out and it doesn't do it...:willy: drives me wild when I take it in and they "don't hear it" OR "cannot duplicate" customers concern...:devil: