Hi all, I've searched high and low for an answer as to what this sound it but maybe one of you can say whether it's normal or if something needs attention.

Basically intermittently I will hear what I can best describe as a "Wookiee" sound. It is typically brief but comes and goes, doesn't seem to matter if engine is cold or warm. If I rev the engine during the sound it does seem to go away, but it's tough to say for sure. I was thinking a pulley/bearing but based on how it comes and goes I'm not confident in that.

I keep trying to catch a video of it but like all good noises it doesn't want to cooperate. I managed to catch a quick bit of it in this video, the noise is at the 6 second mark and lasts about a second or so. Any help is appreciated!

Noise from engine

 

I definitely heard the wookie, or is it wooky?...and it's not a normal sound.

A trick you can try to help find exactly where the sound is coming from is to use an object as a stethoscope. Lisle sells AUTOMOTIVE stethoscopes exactly for your purpose, here Wookie Finder.

If you don't want to shell out the $15-$20 for one, you can improvise by using a length of wood, metal conduit/pipe, short baseball bat, almost anything, and CAREFULLY touch the device you're inspecting (alternator, Power Steering pump, etc) while placing your ear on the end of the wood, pipe, etc, that's touching the object. Obviously, don't touch the rotating part or pulley of the device!

 

A long screwdriver also makes a good makeshift stethoscope. My car once made a similar sound and it turned out to be a fluttering emissions hose that was collapsing. Sounded like a helicopter.

 

Also, can hear what sounds like a whining sound from the 2 second to 5 second mark before the "Wookee" sound at the 6 second mark. Maybe check the PS fluid level for the heck of it....? (Issues with PS pump, H2O pump, alternator, or AC may cause whining.)

 

Thanks everyone! If I get some time to play with it I'll try to give some individual components a listen. I'm coming up on the second timing belt change so if nothing else I'm glad you all were able to hear it and confirm it's not normal. This way if I can't solve it I can make sure he makes an attempt to address it during that process. If anyone else has had this noise please let me know what you ended up finding!

 

Is the AC totally off? (including defrost)

Sounded to me like an AC clutch bearing, maybe.

 

I think you're on to something there! I could have sworn I have heard it without the A/C but today I was messing with it and could pretty reliably reproduce the sound by turning the A/C on and off. Is the A/C clutch bearing a tough job?

 

LS430 AC rotates with the drive belt, using a solenoid to control the flow of refrigerant without a clutch. Is your vehicle an RX350?

 

From another thread ...

 

This is an LS430, and that is interesting information! So I guess then turning off and on the AC wouldn't affect that noise?

 

If you're sure that turning on/off the AC makes the noise appear consistently, it could be anything that is driven by the serpentine belt. (Changing the load on the AC compressor changes the dynamics of everything that is also driven by that belt.) I would get a cheap mechanic's stethoscope to track down the sound. Remove the big plastic air intake over the radiator and carefully listen to each of the belt-driven components (AC compressor, alternator, idler pulley, PS pump, etc) while the engine is running. If you're lucky, it's just the idler pulley, which is a common failure point but cheap and easy to replace.

 

Turning the switch on and off DOES have an effect on the system. Yes, the output of the compressor is variable via an ecm controlled solenoid. However, there still is an electrically engaged clutch inside the AC pulley. The outside of the pulley is always spinning while the engine is running, just like every other car on the road. If the AC button is off that's all that's spinning. With the AC button on, the clutch is engaged and the compressor internals are spinning with variable output.
Sounds like you may have a bad compressor clutch. Once the friction material wears away you are left with metal to metal contact, similar to severely worn brakes. Unfortunately the compressor clutch doesn't seem to be available separately. Time for a new compressor if that's the issue

 

I think that's definitely where I'll start. I'm feeling like it is the compressor so I should be able to find out fairly quickly, but hopefully it is something else!

That clears it up for me a bit, a clutch makes total sense. Unfortunate though!

 

Was thinking about 2006 owned, but depends on the year of your LS430 ...

 

It is a 2004. Thanks for that sheet, according to that it definitely seems like I'm looking at a new compressor. BUT while we're talking about it, is there any reason to replace the compressor before it totally dies? Aside from the noise it seems to be working fine.