Help diagnosing squeal/chirp

[ctoombs]

Hi all,

Trying to diagnose a chirp that seems to be coming from my accessory belts.

Captured a video here and hoping y’all can help point me in the right direction.

Belts are tight and tensioned correctly, alternator was replaced recently. Timing belt and water pump replaced not long ago either.

My initial suspicion is an idler going bad but not sure what one or if that’s the case for sure

Video is linked belowStrange squeak 99 4Runner - Album on Imgur

 

[plcfcng]

When does the noise happen? At start up or other time

 

[ctoombs]

At idle once warmed up all the way.

 

[spartacus]

Sound to me like a'pulley bearing going out or misaligned. Any work done on the engine recently? To me it seemed louder near the fan clutch pulley. take one belt off at a time and see if you can narrow it down.

 

[shadow247]

At idle once warmed up all the way.

These engines are really nice because they have a belt for each accessory, so you can easily troubleshoot the noise.

Just start removing the belts 1 by 1 until the noise goes away.

If you get all 3 belts off, and it's still there, you know it's something behind the timing cover.

Easy peasy!

 

[plcfcng]

A easier way is to use a spray bottle with windex start the engine spray each belt one at a time and listen if it’s a pull-up noise it will quite down for a bearing a section of Heater hose may help locate the noise or as mentioned above remove each belt one at a time. Hand spin each item. The ac idler pulley can be repacked with grease in a pinch

 

[ctoombs]

Bit of an update: ran an errand today where I got fully up to temp, and lo and behold, zero noise.

Now the interesting factor here is it’s 20 degrees warmer today (60) vs yesterday (35-40).

Gonna definitely get into it and see what’s causing the chirp, will report back once I get to the bottom of this.

 

[shadow247]

Bit of an update: ran an errand today where I got fully up to temp, and lo and behold, zero noise.

Now the interesting factor here is it’s 20 degrees warmer today (60) vs yesterday (35-40).

Gonna definitely get into it and see what’s causing the chirp, will report back once I get to the bottom of this.

Please let us know what you found. There are so many threads where people give different kinds of advice, and OP never responds if they tried any of it, or if they even fixed the problem.