Squealing noise on first startup.

[WannaCruise]

Hello all,

I have a squealing noise when I first start my LX470 each morning. It typically goes away after a few minutes, but it is getting worse. It's definitely coming from the Passenger side, and it seems to be the PS pump, or at least that side. I assume it could be the PS pump bearings, the alternator, or the idler pulley in that area, but it does change pitch when the wheel is turned.

Since the alternator was replaced with a Denso unit 1.5 years ago, I doubt it's the alternator. I'm about to order a replacement PS pump, but I wanted to get a sanity check from you guys before dropping $300 on the pump.

Here is a video of the sound from the area:


Here is a video of the sound when load is put on the pump by turning the steering wheel:



Any thoughts, or should I just pull the trigger on a new pump?

 

[Mike NXP]

Dont just throw a pump at it, you can diagnose it easily...It could be your pump but since you asked for a sanity check you should start with the more likely to fail which is your idler or idler / tensioner

If I were you I would start the engine cold and confirm the noise is happening, then I would :
- Spray a squirt of water on belt, does noise go away? Probably not but if it did it could just be your belt / tension

Turn off motor with noise still happening :
- Remove belt with 14mm and breaker bar, Do you have experience with this or need advice? When removing the belt, feel for a good bit of tension, if no tension or bound up you have a tensioner problem

With belt removed, start engine, did noise go away? Hopefully it did.
>> If it didn't, then you have timing belt related issue
>> If the noise did go away, then you can confirm it's something that the serpentine belt spins making the noise

Testing accessories
- Spin your idler. IT shouldn't free spin like a skateboard wheel. It should only go a half turn or so and it should feel firm. It shouldn't be hard to turn , but it shouldn't just free spin. @2001LC has a good video somewhere of this ( and everything else for the 100 series lol)
- Spin your tensioner pulley, same as above , no free spin

Those are the two pulleys that are first to go and cause noise
- You said you replaced alternator so should be able to check that off the list but spin it anyway
- AC compressor, honestly I'm not sure how this should act with no belt , I think it should free spin smoothly
- same goes for your suspect Power steering pump, spin that pulley and see how it feels

If you end up swapping PS pump remember there is a little air vane doo-hickey on the backside with two vac lines, its brittle and usually breaks, may want to make sure new pump has it or order a new OEM part

 

[WannaCruise]

THANK YOU for the very through response @Mike NXP!

I am going to proactively replace the belt, idler, and tensioner pulley as I have them in my parts bin waiting to be done at my timing belt service. It's not too far off from that service anyway. I'll report back with those results ASAP.

I'm trying to get it diagnosed before the 25% off Toyota parts ends tomorrow

 

[WannaCruise]

I did the water spray test and it immediately quieted the belt so I swapped in the new one and the noise is gone. I'm such an idiot... it's the most basic of basic troubleshooting, but the old belt looked to be in pretty good shape so I just assumed it was OK as well. No cracking on the ribs and the smooth side was slightly discolored.

That being said, I did test the pulley's when the belt was off and the tensioner was smooth but did allow for about 2-3 rotations before stopping. The Idler was a little more noisy, and would freewheel for 10-20 seconds... Unfortunately I was wrong and I DIDN'T have the pulley's (I had the timing belt ones) so I couldn't replace it immediately. I'll add it to my order and swap it in ASAP.

Thank you again for the sanity check @Mike NXP

 

[Mike NXP]

I did the water spray test and it immediately quieted the belt so I swapped in the new one and the noise is gone. I'm such an idiot... it's the most basic of basic troubleshooting, but the old belt looked to be in pretty good shape so I just assumed it was OK as well. No cracking on the ribs and the smooth side was slightly discolored.

That being said, I did test the pulley's when the belt was off and the tensioner was smooth but did allow for about 2-3 rotations before stopping. The Idler was a little more noisy, and would freewheel for 10-20 seconds... Unfortunately I was wrong and I DIDN'T have the pulley's (I had the timing belt ones) so I couldn't replace it immediately. I'll add it to my order and swap it in ASAP.

Thank you again for the sanity check @Mike NXP

View attachment 4094416

View attachment 4094417

Nice , fingers crossed the problem doesn't come back and that's all it was.... Backside of the belt does look a bit worn..

Tensioner pulley sounds like it checks out. Top idler spinning 10-20 seconds isn't great but luckily that's the easy pulley to swap. Make sure the orientation is correct some people install in reverse... Hardest part is sneaking the belt back on without removing anything down below.