SoCalSC4

More than likely, it;'s the belt tensioner assembly. After I replaced the belt with no decrease in noise, I spoke with a Lexus technician. He told me that the return spring in the tensioners get weak after a number of years/miles, causing the belt to slip a bit.

I had the "tensioner pulley assembly" (about $135) and the upper idler pulley replaced (as a precaution, on the advice of the Lexus technician I spoke with) during my timing belt/timing belt tensioner/water pump/ thermostat/radiator replacement service and the noise is gone. I did not have the dealer perform the service, I just purchased the parts from them...

I think lubricating the pulley is a temporary fix at best.

DASHOCKER

iTrader: (2)

i tried the wd-40. It still squealed but, but not as audible. I figure i will have to saturate the belt and pulleys some more.

DASHOCKER

iTrader: (2)

The quealing only takes place during the cold weather below 30 degrees. During the warm climates, it does not happen at all. Did the squealing occur during the warm weather for you? I would hat to spend 135 bucks uneccesarily.

jonathancl

I am having this precise problem. It is not the belt or the tensioner.

I have replaced the idler pulley ($85), but it still squeaks on cold mornings.

Lubricating the pulley only stops the problem temporarily.

My next change will be to remove the metal cover in front of the idler pulley to see if the sound is caused by friction between the pulley and the cover.

Update: It was the belt after all. Spraying the pulley as I was must have lubricated the belt enough to stop the squeaking. A new belt fixed the problem.

lexxtasy

Hi guys,
I have a GS300 93 and have the same problem . . . I live in Toronto and it has gotten down to as low as -30F in the past month and thats extremely cold . . . but usually it hovers around the single digits minus temperatures . . .
I have overhead parking for my lexus but its still open so the poor baby sits out in the cold
anyways I hear this high pitched squeal every know and then on my morning start for the first 30 seconds which is what iam really concerned about. . . but after that I usually hear just like low pitched squeals coming from the pulleys which do not sound as dangerous and concerning to me because they go away after the RPM gets below 1000 . . . infact I let the engine idle for a good 5 mins every morning considering the age and mileage of my car which is close to 200K now . . .I dont wanna take any chances . . .
But having so read the posts above apparently changing the components of the drivebelt region dont seem to have any impact on the squeal noise either!
but there was a suggestion made for the WD-40? where excatly will it have to be sprayed because I did open my engine a couple of times to see where exactly the noise is coming from but cudnt determine the source so if someone can please help me with where to spray the WD-40 in order to get rid of this squeal
Thanks

RRocket

Someone sells the idler bearing for our cars on E-bay for like $23...

EvilRyu

I'm having the same problem. Can anyone answer his question? thanks

DASHOCKER

iTrader: (2)

On the the upper pulley near the intake tube. Spray the wd40 where the belt makes contact with the pulley. soak with the wd40. spray it on all pulleys wher belt makes contact. It will not cause the belt to slip at all. It is a temporary fix though. will last about a week maybe.

DA51

NAPA carries sealed bearings to replace both idler pulleys. Part numbers are important.
Replace both at the same time since you have the Belt off.

XxSC400xX

iTrader: (1)

What's the price on those bearings?

Edit: Nevermind I found the answer.
https://www.clublexus.com/forums/performance-and-maintenance/59915-noise-in-the-engine-bay.html

G430

i know how it is in the NE area i live in Mass and @ the cold start it really did squeal like pig.. yes have embrassing to the lexx but i fix mine .. yes my father and i were working on the car then there's a pulley on top"under the factory intake" i aint sure what to call it but there's a bolt in the center where if you tighten it the pulley has a spring that lowers the pulley where you can change the serpintine belt and ever since i tighten the bolt there's no more noise.. ill do my best to get some picture i work alot too but ill try

engin_ear

iTrader: (1)

And my personal fav:
• Removes a Boa Constrictor stuck in engine compartment of cars

I missed this thread first time around. Johnny has too much time on his hands.

lexoman562

iTrader: (5)

i have an 01 gs300 and have the same problem , only squeels in the moring , whether its a cold or hot morning , i sprayed wd40 on the bolt took the noise away for like a week , then it came back . now i just deal with it , kinda sucks though when ur at a red light and my car is making that noise...

Blizzy

iTrader: (-1)

This is an OLD, OLD thread, and I apologzie for bringing this back to the surface. But, this advice was just what the doctor ordered for me.

Yesterday, my 96 SC400 started squealing a little bit (30-40dB) at idle along the serpentine belt. I listened carefully to identify the pulley that was the culprit, sprayed some WD40 near the point about which the pulley was rotating, and BAM! I fired her up, and there was no squeal.

This is excellent advice!

GSteg

iTrader: (15)

WD40 is a temporary solution.

Getting a new belt is the fix