GSquicksilver

Fellas,

My 93 LS400 starting squeaking in the engine bay today. I thought it was the serpentine belt, so I sprayed some belt conditioner on it, but it still keeps squeaking. I'm worried that it could be in the timing belt area. Could it be the timing belt pretentioner bearings? Has anyone ever had this problem?

RA40

iTrader: (6)

Any change in pitch or frequency relative to engine RPM?

Could be any one of the pulley bearings. What mileage are you at?

GSquicksilver

i'm at about 165k miles already. i haven't noticed if the pitch changes if i increase the rpm. i'll check it out in the morning.

ChuH

The common problem is the idler pulley. I had this problem with past and present Lexus (95 SC400 and 01 GS430). This pulley is located near the top closed to the intake and radiator hose. To make sure simply spray some white lithium grease or WD40 (not a long standing lubricant) between the front plate and pulley.

Chu...

Rice

It's most probably one of the timing puleys.
I have the same problem. WOW, I've been saying this alot lately!
First, I was hoping that it was one of the accesories on the serpantine belt. So, I removed it, but the squeeking, or rather whining at low RPM, remained.
In case you deside to make sure that it's really one of the timing puleys and decide to spray some lubricant on them, DO NOT DO IT! Your timing belt might slip and cause all sorts of problems.

GSquicksilver

man, my car is weird. today there was no sound at all. wonder if this is intermittent. that would totally suck. thanks all u guys for ur inputs.

GA400

My 1991 LS400 started squeaking just a bit at startup, then occasionally while I was driving. Sometimes it would stop altogether for a couple of days and I would think it had stopped for good, only to reappear eventually. I thought it was an idler or tensioner since it seemed to speed up with acceleration. It turned out to be a bearing in the water pump, which seized a couple of weeks later, taking the timing belt with it. No permament damage done, thanks to the non-interference design of the engine, but I had to have it towed to my mechanic and it scared the heck out of me. It was a very noisy, violent sounding failure when it went, and I left a big stream of environmentally hazardous coolant on the ground. I would have a master tech listen to it and give you his opinion.

Good Luck,

Rich

Colby

Another thing worth looking at is the A/C. When the car is not squeaking, turn on the A/C. If the squeaks suddenly appears, you know that's the problem.

Colby

wetwax

Check to ensure your Flywheel is torqued properly. I had my timing belt changed on a 1994 LS400 at the dealer. When they re torquedmy flywheel the squeek was gone.
Best of Luck

Wetwax.

Rice

I wonder how did they get to your flywheel while changing timing belt?
To torque the flywheel they had to remove the tranny.
Sounds like they told you one BS story!
I hope they didn't charge you extra for this.

brit_lex

Hi,

My 92 car has chirping noise coming from the engine. It has got worse over the last 2 years. Water pump has been replaced 50,000 miles ago along with cambelt.

Do you think it's the idler pulley? If so, is it just a matter of buying the 2 idler tensioners for these models? Could I change the tensioners at home on my own (I can change spark plugs but that's it!)?

Thanks.

ChuH

I am pretty sure it is the idler pulley. Just had my done under warranty about 3 weeks ago. Dealer replaced two pulleys (idler and don't recall the name for the other pulley), belt and radiator coolant (I guess they had to move one of the hose to remove one of the pulley). My past 2 Lexus ('95 SC400 and my dad's 95 LS400) all had the idler pulley replaced.

Chu...

brit_lex

Does the chirping noise disappear completely then? I notice it most when I'm stopped at the lights in D with the window down. The noise increases most when you go from P to D.

ChuH

My sound only happens in the morning after a overnight rain. As the engine heats up after a few minutes the noise disappears. Noise decreases when I go from P to D because of slower rpm. To see if it is the idler pulley lightly squirt some lithium grease or WD40 using one of the included small straw to direct the lubricant between the front protective plate and pulley center where the bearing is (DON'T SQUIRT AT THE BELT!!!). If the noise disappeared then it is the idler pulley. The pulley bearing is quite cheap. As I recall when I replace it on my SC400 it cost about $25 to $30 for the bearing excluding labor which took less than a hour by the dealer.

Chu...