Help with diagnosing AC compressor whine. (1 Viewer)

[birch hill]

Hello, recently purchased a 2006 Lx470 with 89k miles. Im not overly familiar with these cars yet but, coming from a Land Rover Discovery, I am prepared to learn and do my own work. The car is making a high pitch whine when accelerating It gets audible when accelerating, first showing up at 2k rpm and up and sounds like a supercharger. It only does it with Ac on and immediately stops if I switch AC off. I have searched and have not come up with a conclusive answer. Is this indicative of any known problem ? Could the compressor be going bad with only 89k miles? Any help with where and how to start diagnosing this would be greatly appreciated.
Thanks!

 

[outdoorsman]

Is it a belt or a bearing sound?

The noise may or may not be coming from the the A/C compressor. When the A/C kicks on it puts more of a load on the belt. It could be anything from tensionor (which has an updated design), idler pulley, fan bracket, alternator or power steering pump.

You can use a stethoscope or screwdriver to narrow it down.

If you can narrow down we will gladly help you fix it.

Please as always let us know what you find out.

 

[birch hill]

Thanks. Using a length of copper pipe to listen while someone accelerated the rpms. The noise seems isolated to ac compressor. Noise is loud making it a bit hard to 100% isolate. It’s kind of a whine crossed with a mild grind. It immediately quits when ac shut off. Definitely significant vibration to the ear through the pipe while on compressor.

 

[birch hill]

Also, can the ac clutch be slipping grinding? Are they replaceable separate from the compressor?

 

[outdoorsman]

OK

Do you know if someone has changed the timing belt lately?

There is something it would check before I would replace the A/C compressor or clutch. There are 2 long bolts that go through the A/C compressor and go the the fan bracket. They both have to be removed when changing the timing belt. They are kind of hard to locate the bolt heads. You will need to remove both underbody splash shields the metal and plastic.

Check for these bolts to be loose or missing.

I purchased a 04 LC last year for my son and swore it had a bad a/c compressor. I was ready to order one.

While chasing a water leak near the water pump. I went to remove those bolts and they were both loose and one was ready to fall out. Others have found the same problem.

If it is not the bolts being loose then you are right there to locate the issue.

 

[birch hill]

Ok, the timing belt was just replaced about 4K miles ago. Will check bolts. If not the issue is there away to isolate the ac clutch as the problem and is it replaceable separate from the compressor.?
Thanks

 

[outdoorsman]

Bolt locations

 

[birch hill]

Great thanks. What book are those images from?

 

[outdoorsman]

Here is a replacement Denso compressor with clutch.

Denso 471-1220

https://www.amazon.com/Denso-471-1220-New-Compressor-Clutch/dp/B001UCBMJK

 

[outdoorsman]

A/C Clutch OEM part # 88410-60410

Clutch - Toyota (88410-60410) | Toyota Of Dallas

 

[birch hill]

That’s not bad. I wonder if there is a way to tell if it’s the clutch or the compressor.

 

[outdoorsman]

If you take the belt off and spin the compressor clutch pulley you can usually tell if it has a bad bearing.

I am just thinking with only 89K miles I have a hard time believing that the clutch or compressor is the issue. I guess maybe they could go bad if they sit a long time unused.

The timing belt and water pump should be replaced every 90k. They was leading me to think maybe some changed it recently. If not you are due for that.

Also change out the 2 plastic heater T’s on the back side of the engine near the firewall. They become brittle with age and can cause the engine to overheat with devastating results.

 

[birch hill]

I’m surprised it would already be bad too. The water pump and belt where changed at 86k miles. Thanks for heads up on heater “t”s. If bearing was bad wouldn’t it make a racket all the time. Noise only happens with ac engaged and revved over 2k rpm

 

[birch hill]

I guess I will order compressor. Maybe try changing clutch first and if that doesn’t fix change while compressor. Is the 471-1220 correct with having rear ac?

 

[bigredmachine]

I guess I will order compressor. Maybe try changing clutch first and if that doesn’t fix change while compressor. Is the 471-1220 correct with having rear ac?

should be the same compressor with or with out rear air

 

[outdoorsman]

Denso 471-1220 is the correct part number for compressor for a 2006 LX 470.

Also rear air was standard not a option on 2006 LX

You will also need to replace the dryer Denso 478-1500. It is located on the condenser in front of the radiator.
https://www.amazon.com/Denso-478-1500-Receiver-Drier/dp/B000IWLAB8

It also is recommended when replacing the compressor to replace the expansion valve Denso 475-0508 located in the passenger side behind the glove box. It is a kind of a PITA to get to.
https://www.amazon.com/gp/aw/d/B000...s=475-0508&dpPl=1&dpID=31TAVVHC33L&ref=plSrch

You will also need to rent a vacuum pump from a auto parts store.

Denso part look up link
Find My Part

 

[birch hill]

Thanks. I ordered all 3. Plan is to take off the clutch from new compressor and try that first. If that fixes it I send other 2 parts back and have a spare compressor sans clutch and a lot less work. My brother does residential hvac so I plan to get him to pump it down and recharge.

 

[birch hill]

From what I have been reading the compressor has to come out of the car to replace clutch? If that’s the case I will just replace the whole compressor assembly. Any know if clutch can be changed without removing compressor?

 

[AZSlim]

What happened?

 

[sandslx]

@birch hill - Any know if clutch can be changed without removing compressor?

*** Bump for update ***