BCT

Hi all,
My 02 SC430 with 183K suddenly has develop this whining sound since this afternoon. I replaced the serpentine belt, thinking that might be the cause but no luck. Any idea what is the problem? Or how to troubleshoot this?

https://www.dropbox.com/s/mdrduzse8y..._0928.MOV?dl=0

Thanks!
Chris

Coleroad

BCT

Thanks Coleroad! Power steering fluid is full.
I am going to pull the belt out again and try to isolate the problem. I spun the tensioner and idler pulley by hand and they seems ok. I did not spun the alternator though.

Htony

Idler or tensioner bearing? Old belt was loose and now new one is tighter. Good luck.

malema

I second the Idler, tensioner pulley. Really sounds like a pulley rather then the "slip" that bad belts make

VVTiBob

john341

Did you wash the engine bay before this noise started? To me it sound like a alternator whine. if it is safe you can unplug the alternator and see if the noise goes away. If washed wait couple of days and see if the noise goes away.

BCT

So... the sound is still there

I have replaced idler pulley (it was not spinning very smoothly when I took it out and spin it with my hands) and serpentine belt. I was going to replace tensioner pulley as well, but local store do not have any in stock. The guy at Napa think, after spinning it by hand, this is not the issue.

I also ran the car for a few seconds without serpentine belt. It did not make the noise.

Did you wash the engine bay before this noise started? To me it sound like a alternator whine. if it is safe you can unplug the alternator and see if the noise goes away. If washed wait couple of days and see if the noise goes away. I started the car without the serpentine belt, and there is no whine. I am thinking maybe alternator? I have not washed the engine bay. The car is park in the garage, and do not go outside when raining. The noise started as I was driving home at around 35mph after dropping of my son at school. So I drove it for maybe 2 miles at the most to get home.

How does the sound change as the RPM go up? Down?
When the RPM goes up, the whining is also going up.

Would dark power steering fluid cause this whine? When I bought the car, I remember the fluid was very dark. I have replace the fluid, but notice today, while it is still red, it is darker than new fluid. It is full though. Would flushing the fluid again help?

Next step, I think I am going to see if I can borrow some stethoscope. I was going to borrow one at Napa, but I was there as they were closing.

Lmk if anyone have any thoughts on this...

Harold57

Yes, it may require a few flushings to clean up the power steering fluid. The crud sticks to the walls and so will hang around for the next fluid.

Bgw70

BCT

Hey all,
I am in the middle of trying to remove the alternator since yesterday. Looks like I need to remove the power steering pulley according to this post (step 3, second picture) https://www.clublexus.com/forums/sc4...ml#post9806865

I got the power steering pulley nut off but the pulley is stuck. How do you get this pulley off? Do I need a puller? I am not sure there is enough space for a puller without disconnecting the big radiator hose.

Appreciate any help!

BCT

Just to close the loop here. I ended up calling a mechanic who used a puller. The PS pulley was stuck pretty good in there. I am guessing maybe the previous person who did this over tighten the nut plus some corrosion too. The alternator does not seems original one.

Harold57

So is the whining sound gone now?

sixonemale

I'm getting this exact same whining sound when starting the SC cold, but it tends to almost go away when warm and I think at higher RPMs, I will do more testing over the next day or two.. Our SC has about 89,000 miles on it and my wife is the primary driver of this car. I generally drive it to have it washed and fill it with fuel, and on occasional weekend road trips, etc. Because the timing and drive belts were replaced about 12,000 miles ago, I don't think it's a pulley associated with timing belt. The power steering and brake fluids were flushed and replaced about two weeks ago. My first guess was the alternator/generator so if that solved the problem for BCT or if anyone else has any insight or thoughts please feel free to post. TIA

Update: I took our SC to the local Toyota service center and described the problem to a seasoned service advisor and he said he had owned a LS400 and what I described sounded like the alternator/generator bearings going bad. I'm going to get it diagnosed and repaired on Monday and will let the forum know the outcome.

Update II: No noise this morning so I'm going to hold off taking it in to be diagnosed. Fortunately/Unfortunately it needs to be more consistent vs intermittent.

sideswipe

Same problem just started with me a couple of days ago but now its gone. I will see how it goes and let you all know.