Screechy hissing noise from AC - with video!
#16
#17
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The video is not loading for me because im at work right now, however i know there is a hissing noise that results from broken servo motors. These are the same motors that regulate the cool/warm air flow into the cabin.
Also, do you know any of the OEM AC components have been replaced?
Also, do you know any of the OEM AC components have been replaced?
#20
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I just got back from the dealer and showed the noise to the tech. He said that he makes no guarantees, but it amy be to a low level a refrigerant in the system. He said that on other cars, it usually gets rid of the noise if it is infact the case. And yes- some cars are more audible than others. Mine is pretty loud
#21
Pole Position
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If you're concerned by it I'd suggest taking the car to an A/C place (over here most auto electrical workshops do A/C also) and having them check the system's high and low operating pressures. If all is within spec it's likely a sticky TX valve.
Justin...
Justin...
#22
Instructor
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I have the same noise. It is only audible when the AC is on. The noise is not related to the fan or air flow. The accessory drive belt is not a factor in the noise (in my situation, at least) because I changed it out with a brand new OEM one and it didn't change the noise.
The most plausible explanation for me is as stated above - "You might just be hearing the gas atomizing at the metering valve of the evaporator coil."
The most plausible explanation for me is as stated above - "You might just be hearing the gas atomizing at the metering valve of the evaporator coil."
#24
Instructor
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Since it is a closed system, if the refrigerant is low, wouldn't that mean there is/was a leak somewhere? Did they perform a leak test on both front and rear AC?
For those that want to check for insufficient refrigerant, run your engine @ 1500rpm, set front and rear blowers to HI, driver/passenger/rear AC to MAX COOL, and fully open all doors. Look through the sight glass and if bubbles exist, you have insufficient refrigerant (unless ambient temp is higher than usual and cooling still works).
#25
Lexus Test Driver
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This was two years ago, I was missing about half of it. Got it done at independent mechanic. He couldn't find a leak, it must be a tiny one. I've been having another issue though, my A/C takes about ten minutes to start blowing cold air. It only does this if the car has been sitting for a long time, like overnight. Nobody can figure out what is wrong with it. I just had it recharged again, it was 2lbs low. The delayed cooling problem still exists, and the noise has come back too. I think maybe the tiny leak has now gotten big and I've lost a lot of refrigerant again. I have to take it back to the shop and see if they can locate the leak and find out why it takes so long to start blowing cold air, even when it has full refrigerant level.
#26
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Update: Problem fixed!
I am the original poster.
Thanks to responses, I asked the dealer to recharge the AC and the noise went away. The tech did not think recharging would fix the problem so I had to promise not to hold the dealer accountable if the noise remained.
Thank you. I like my car again.
I am the original poster.
Thanks to responses, I asked the dealer to recharge the AC and the noise went away. The tech did not think recharging would fix the problem so I had to promise not to hold the dealer accountable if the noise remained.
Thank you. I like my car again.
#27
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Update: Problem fixed!
I am the original poster.
Thanks to responses, I asked the dealer to recharge the AC and the noise went away. The tech did not think recharging would fix the problem so I had to promise not to hold the dealer accountable if the noise remained.
Thank you. I like my car again.
I am the original poster.
Thanks to responses, I asked the dealer to recharge the AC and the noise went away. The tech did not think recharging would fix the problem so I had to promise not to hold the dealer accountable if the noise remained.
Thank you. I like my car again.
#28
Lexus Champion
iTrader: (20)
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Update: Problem fixed!
I am the original poster.
Thanks to responses, I asked the dealer to recharge the AC and the noise went away. The tech did not think recharging would fix the problem so I had to promise not to hold the dealer accountable if the noise remained.
Thank you. I like my car again.
I am the original poster.
Thanks to responses, I asked the dealer to recharge the AC and the noise went away. The tech did not think recharging would fix the problem so I had to promise not to hold the dealer accountable if the noise remained.
Thank you. I like my car again.
#29
Lexus Champion
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It is virtually impossible to have an absolute seal on high pressure gas (liquid is entirely a different matter and very easy to have an absolute seal). The leak is very small and is allowed by Lexus specs. Over a matter of a few years, the freon level can be expected to be low. When they recharge a system they generally add a dye that is detectable with a UV light so they can find an excessive leak. Really the only check the technician can make is to visually confirm that there are no air bubbles in the sight glass and then check the A/C discharge air temp to confirm that it is in spec.
Just a good idea to have the system checked and recharged every other year at least.
Just a good idea to have the system checked and recharged every other year at least.
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