Single sqeak on start up

[avacado11]

when I start my car(Lexus is250) in the morning I get a single chirp/squeak about 1 second after the engine starts idling. Everything's fine after. No squeak, no chirp.

Im very sure my belt is original(almost 6 years old, 68k miles). Checked the belt, there's still good tension and no cracks. So I'm gonna assume it's a pulley.

Is this something I should be worried about? Does that sound more like a bad belt or possibly not belt/tensioner related? Trying to narrow down the possibilities. Any belt/tensioner work on this car requires taking a bunch of stuff off.

 

[Dave9]

You should be able to visually examine the belt to see if it looks worn out, but at the age and mileage, it could easily be worth the piece of mind to go ahead and replace it.

In some cases the tension can look good but the tensioner doesn't move freely, especially when it gets colder outside. This commonly causes startup squeal, but so could a bearing on whatever.

How worried you should get depends on how bad a predicament you'd be in if the bearing seizes and throws or shreds the belt and leaves the vehicle inoperable wherever you might be at the time. If you have electric steering then it's not quite as bad if it happens while driving. as it would be for someone, particularly a small female or elderly person, who suddenly had to put some muscle into steering because their hydraulic pump is no longer power assisted by being belt driven.

The typical way to dig into this is pull the belt off then start the engine. If you still hear the noise then it's not something belt driven. Spin all pulleys and feel for tightness, roughness or wobble.

Considering the age of the belt, if you're pulling it off anyway to check this, I'd go ahead and put a new one on while I'm at it. If putting a new tensioner on isn't TOO much extra trouble or expense then I'd do that too.

If you just want to let it go for now, that's an option remembering the chance of getting stranded somewhere. Depending on what it is, it could go for years before something causes that, but I would at least get a strong flashlight and look carefully at all pulleys to make sure none are wobbling during idle. Anything bad enough to be wobbling, there's not much sense in waiting to fix that.

 

[avacado11]

Took a closer look. Seems to be a pulley from how metallic it sounds. I assume if it was a belt it would squeak as soon as the engine starts idling, this doesn't happen until a second later then goes away.

Guess I'm taking it apart this weekend and figuring it out

 

[tiger862]

Tensioner is probably sticking in fixed position and after starting it frees. Easy to check as you just try to move tensioner as removing belt then release to see if it tightened up the belt.

 

[fsdork]

I am interested in the replies to this thread, as I have the same issue with my F-150. Only on stone cold starts, and always a single chirp a second or two after starting.

 

[dishdude]

PS pump, it's normal on super cold mornings.

 

[avacado11]

Originally Posted by dishdude
PS pump, it's normal on super cold mornings.


My car has electric steering so it wouldn't be that.

Went to autozone and picked up a new belt. It did NOT fix the issue. The tensioner spring still feels good with no play, but I noticed that the tensioner pulley had slightly more resistance than any other pulley. Still spun freely but would stop quicker than others.

The whole tensioner seems to be a major pain to remove. Is there some sort of stop sqeak I can throw on the pulley? I know it's not ideal for the belt...just looking at all options right now. The noise is non existent when warmed up, not even sure if it's worth messing with until it gets louder

 

[FT92]

my accord does that about once a month...usually after sitting all night...a small chirp/squeak on start up...I've changed belts ,just had the timing belt and all associated goodies changed about 1k miles ago...I cant seem to find anything wrong..so I just went with the old saying "if it ain't broke don't fix it"

 

[Linctex]

My guess is it happens when the field gets energized on the alternator.

It doesn't start charging until after the engine is running.

 

[avacado11]

Ok so after really taking it apart and checking everything again, it turns out to be the AC compressor clutch once it engages. This explains why it takes a second to squeak instead of being instant as the pulleys start turning.

I had this happen before on my Subarus....can't remember if it means I need a recharge or if the compressor clutch is starting to show its age. I do run AC pretty much all summer because it's soo d*mn hot in Arkansas every day.