watermelon

IS250 2007 w/ around 127k miles

I have been experiencing this chirping noise from my engine area for a while now. When I leave it in park, the noise is less subtle but when I put it into reverse or drive, the noise is significantly more noticeable. Sometimes, the noise would disappear as well. The noise is gone once I start driving or reversing. I remember when I blasted my AC on high, it caused unsteady idle and kind of a jerk movement. When I looked up the possibilities, some said it might be the alternator or alternator pulley dust build up.

I would love for some inputs. The car drives perfectly fine but I'm just concerned about the chirping noise since it is unnatural. I go to school in Irvine, California so if you know some reliable mechanics around OC, please let me know so I can bring it in to get it checked. I was quoted 100 something for an inspection of the problem in a shop in Irvine but I thought I'd ask for some input and recommendations before doing anything silly since I am a college student. I have attached a video to show what it sounds like.


Thanks all!

WhatYaGot

I have the same random chirp. 2006 IS350 w/ 238,000 miles.

primavera

If you pop the plastic cup on the alternator pulley and blow off the dust, that may fix the chirp. (0:18 sec in the video)

sktn77a

iTrader: (2)

Sounds like an idler/tensioner bearing.

604GSE21

i have it too with 198,000km..

watermelon

Is the alternator pulley on the alternator itself?

5gears-IS

iTrader: (5)

I had the same issue...all I did was spray belt dressing and its gone. I am planing on doing the water pump soon so I plan to change the belt with a new one. I will also inspect the idlers while at it. I'm @ 125k 2006 IS350

2013FSport

iTrader: (2)

Its the belt slipping a tiny amount. Over time the pulleys and belts get glaze on them which allows some slip and the subsequent chirp. A new belt will fix most if the tensioner is working properly.

Belt dressing can also help.
As can spraying a mix of water/dish detergent on it while running. This will induce slippage until the water is dispersed.

Gville350

iTrader: (10)

When I had a random belt chirp, I thought it was a pulley. Purchased the replacement pulley. But before I went to the trouble of replacing the pulley, I installed a new OEM belt I had sitting around. That cured it! New pulley is still sitting in a box collecting dust. LOL!

macjac69

When replacing the belt be careful not to let the tensioner slip and contact adjacent pulley because it will cause damage and create more noise and require eventual replacement.