Greetings. I've had my 08 LS460 just under 3 months. Love it. I've only put roughly 1100 miles on the car since I got it and 170 of that was the ride home from the dealership.

Now that it's colder, I'm noticing something and wanted to see if it was normal. My car is garaged. When I start it up and press on the gas, I get this high pitched whining sound. This goes on for maybe 5 or so minutes before it seems to go away.

Is this something due to the cold weather?

Thanks, Ron

 

Loose belt?

 

It doesn't scream like a loose belt. When I press the gas, the engine has a whining sound to it for the 1st 5 or so minutes.

 

Can be a dry bearing. Open the hood and see if you can find where the noise is coming from.
Inspect the belt as well to see of there are any obvious problems.

These motors are not as smooth or quiet as Ls 400 or ls430 motors. Direct injection is also a noise contributor.

 

Are you using AUX input most of the time by any chance? Going out on a huge limb here...

-Joe

 

Hi. No I don't use the Aux input much. The sound only occurs when i first start the car on a cold morning. When I gun the engine there is a whiny sound that clears up within 5 or so minutes.

 

Ok, I was thinking maybe a ground loop isolation issue. I remember in my RX you could hear the whine while using the aftermarket iPod interface I had, and acceleration increased the pitch and volume of the whine. I have heard this phenomenon in other cars too with various input sources but looks like my idea was not a winner in this instance.

Is there any way for you to capture a video recording the sound?

-Joe

 

There are a few areas I would check.
1. Serpentine belt
2. Idle pulley bearings
3. Belt tensioner.

I place my bets on the tensioner allowing the belt to slip when it's cold. This is usually a telltale sign of a tensioner on it's way out. Belt tensioners can fail unpredictably on all cars, any car and that is just the nature of the part.
Depending on the age of the belt I would replace if you are going to change the tensioner.

 

i have never heard this in an LS460!

i have however heard this in my ls430 and in my dad's gs400 and it occurs right around 35-45 MPH...

 

Hmmmm. Well I may be heading to the dealership. Again, the car isn't driven much. It only started making the high pitch hum when it got colder. It only does it for the first 5 minutes of the ride when I press on the accelerator and then it's perfectly fine the rest of the trip.

I'm stumped.

 

My money is on the Belt tensioner. My car would make that same noise every other month for a limited time then goes away but I don't drive my car a lot working from home so that may be one reason for not hearing more often. I was at the dealer recently and asked my tech to look into it and told me I need to replace the belt tensioner.

 

I know the idler pulley was a recall on my 2007. Perhaps you should check if your car was recalled, and if so was the pulley replaced.

 

The only thing done was the valve springs. No other notes of Lexus recalls for the car. I would suspect if it needed it done, it would have been since the previous owner seemed to do it all.

Update: Today before driving the car (1st time in 2 days), I started it in the garage and let it warm for several minutes. No noise when pressing the accelerator to drive off.

 

You can check here to see if your car was part of the recall -

http://www.lambros.net/LexusTechInfo...SB-0164-08.pdf

 

You wouldn't happen to know if they replace the belt when they do that recall, would you?