GX470GT

98 ls400 engine whines as if there is a supercharger on it. it whines in sync with the rpm's. stops whinning around 2500rpm. idler pully? alternator?

the sound is not very loud, but its there and its annoying!

i can't figure out what pully its coming from. Anyone experience this before?

car has 73k miles

RA40

iTrader: (6)

Unfortunately, this is one of those search and replace scenarios.

GX470GT

thats what i thought. oh man.... i guess ill start with the idler!

etex

While the drive belt is off, check the engine-driven fan for back and forth movement. May be the fan bearing bracket.

1badlex

iTrader: (4)

mine is doing a similar thing but mine is more of a squeek

sethjon

It could be any pulley. you have to remove the belt and spin them individually. A possibility, albeit probably not, is a water leak that is going on to the belt. That would make a high pitched chirp and go faster as you rev the motor.

sethjon

It could be any pulley. you have to remove the belt and spin them individually. A possibility, albeit probably not, is a water leak that is going on to the belt. That would make a high pitched chirp and go faster as you rev the motor. Also possible to be the water pump. When was it changed last?

Silverpaws

I had the same thing happen on a non-Lexus vehicle and I thought it was a number of things including water pump, alternator, pulleys, power steering pump, etc. Turns out that it was the drive belt which had hardened due to heat and age. Was a cheap repair so I would try replacing that first. Those type of noises are difficult to isolate sometimes.

waseem3000

A whine could be related to your transmission mounting or the rear engine mount (as they call it)... happened with me too... have a look at it first as it could be as simple as that... I thought that it was my engine too but it was definitely the mounting...