AC compressor noise

[kcooper]

My 2007 LR3 A/C compressor is making noise from under the hood and can be heard from inside the vehicle. Drive way test confirmed that the actual noise is coming from within the engine compartment and not the blower/ductwork inside. When switched on it sounds like a bearing slightly whining and changes pitch with the engine RPM. Switch the A/C off the the noise stops.

Anyone experienced this? Or found a fix? Wonder if it could be low Freon or the compressor beginning to near the end of it's life?

 

[Houm_WA]

Mine's been like that for a long time (like years not weeks). I haven't bothered to fix it...

 

[Codename Duchess]

I've got some whining now that sounds the same. Changes pitch with RPM, however I've replaced the alternator just under a year ago. Since it's winter now my AC is off anyway, but could it still be AC?

I also replaced one of the pulleys, I wonder if there's another one in there that's giving me trouble

 

[djkronik57]

I have the same thing. From the research that I have done, the noise is due to low refrigerant, not the compressor itself. The rear AC lines often corrode and leak. My plan is to get the refrigerant recharged when summer rolls around and see if that fixes the sound and for how long. Ultimately, it probably means we will have to fork out $$$ for the rear AC line replacement.

 

[Houm_WA]

If it's low REFRIGERANT, does the whining noise occur when the HEAT is running as well? Or would that whining be due to something else?

 

[djkronik57]

If it's low REFRIGERANT, does the whining noise occur when the HEAT is running as well? Or would that whining be due to something else?

The whining due to low refrigerant stops soon after you press the ECON button, shutting off the A/C. The A/C runs with the heat on as well to dry the air and defog, so the real test is to use the ECON button and see if it goes away.

If it doesn't, then it is likely something else.

 

[Houm_WA]

Thanks! I'll have to try that tomorrow...

 

[thorgal]

Had the same compressor noise/whine that changes pitch with RPMs. It was due to low refrigerant .I was one pound short .since I have rear AC my system contains 900 g of refrigerant , so it short I was missing half, but I never ever toped up with gas in the last 10 years and the noise really appeared a year a go.
Obviously , this gas had to disappear somewhere so during a regular oil change I poked around with flashlight and discovered wet spots on two connection joints , one under the door sill and one above front axle, the least accessible spot there is .So now I will be facing three possible scenarios :

-to continue adding refrigerant every year and don't bother

-face the fact , that I need to replace AC pipes or O rings in connection joints which will be very expensive , in both cases ,as access to them is very hard and labor intensive, almost cost prohibitive, unless somebody badly needs rear AC, which I don't,

This brings me to the third option which is to cut off the rear AC system altogether by buying a bypass AC pipe leaving just the front working as many people already did , especially over the Pond.

-

 

[Houm_WA]

If this turns out to be my problem as well, it'll be Option 1 for me.
.