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2006 STS-V
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Discussion Starter #1
Hi - Last winter (I'm in a cold climate), and again this winter, my 02 Deville makes a brief, loud whistle/squeal sound on a cold start, but the sound goes away after 1 or maybe 2 seconds. It will continue to make this sound if you turn the car off & start it right back up again, but stops after a 5 or 6 start-ups. It has nothing to do with the serpentine belts, and does not have anything to do with accelerating or raising the idle of the engine. Once the car has warmed up, the sound goes away, and it will only reappear if the car has cooled right off. It sounds like its coming from the area of the throttle body, so I came to the conclusion that perhaps the starter was the culprit, and that its casing was expanding & contracting with the cold & warm changes in temperature. I very recently noticed though, that if I'd slam on the brakes when driving on a snowy or slick surface, that the sound would again reappear. At that point, I moved towards thinking that it had something to do with either an ABS pump or a Traction Control part that perhaps pressurizes or engages on start-up, and again once its needed while driving, but I'm not really sure. Everything is functioning properly (ABS & TC), and I've even tried to turn the key to "on" for a couple of seconds before starting the engine to see if the noise would appear pre-start-up, but that never happened. I've searched & searched for clues on what this noise could be a result of, but have had no-luck with finding anything anywhere. Everyone who's heard it has said that I should ignore it until something fails, but the sound is a bit embarrassing when people are walking by and I'm starting it up (lol). If any of you have encountered this issue, please send me a reply!!
 

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White Diamond '03 DHS (with DTS floor shift)
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Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

Could be the starter pinion clutch.
Or the AIR pump, but if it only lasts 1-2 seconds, I'm betting on the starter.
 

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2006 STS-V
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Discussion Starter #3
Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

But why would the sound reappear when the car goes into a skid? Btw, it wont make the sound on dray movement when slamming on the brakes...only when its skidding...
 

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2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
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Are you 100% sure it's not the belt? ABS engaging would put a load on the alternator. That could cause a loose/worn belt to slip on the alternator pulley.
 

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98 DeVille, 97 DeVille d'Elegance
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If you dont have any codes very well could be starter pinion. There have been a few that return spring was bad and would allow pinion to contact flywheel, right turns mainly.
I would also check the wp idler pulley as if its going out might be causing the noise.
 

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White Diamond '03 DHS (with DTS floor shift)
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Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

Btw, it wont make the sound on dray movement when slamming on the brakes...only when its skidding...
Now THAT sounds ABS related, but hard to imagine a "squeal" from the ABS.
 

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1992 Fleetwood S&S Hearse, 1993 Buick Roadmaster
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Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

Could be two separate, unrelated issues. ABS acting up causes one sound, a bad bearing or wet belt causing a very similar, but unrelated, sound. I realize how crazy that sounds, but I hear from customers every single day who have two unrelated problems but swear that the one must be causing the other.
 

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2006 STS-V
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Discussion Starter #9
Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

Thanks for all of the suggestions. I started with having someone (who knows a bit about cars), stick their head under the hood as I'd cold start-it, all in an effort of pinpointing where the noise was coming from - I had originally thought that it was the Secondary Air Pump (which doesn't function), and thought that it was coming from the corner of the car before actually looking at it closer. After he listened to it a few times, we switched positions, and he told me to put my ear close to the throttle body, because he felt that that was where it was coming from. After listening, I agreed. I then left the car at my mechanic's over night (there are 2 guys at the shop), and went there the following morning so that we could all diagnose it at the same time, on a cold-start As I started it & they listened, they both concluded that it sounded like it was coming from under the engine cover on the driver's side, and after we looked online to see what was under there, sort of decided that it was the starter. 2 weeks later though after we had a snowfall, I noticed the sound when sliding to a stop. I immediately tried to recreate it by slamming on the brakes, and it kept doing it, but would only do it during a skid (not on dry pavement). Its definitely the same sound because its a unique sound that you'd never hear from 2 different parts. Its not on the belt or alternator side, and again, only happens on a start-up - never when increasing the idle or at any speed. Its a squeal almost like a belt, but its not a belt. BTW, I had the water-pump pulley and belt replaced last fall (it seized), and the noise happened both before AND after those 2 parts were replaced, so its nothing to do with those either. I wonder if there's a way to add a sound clip on here??
 

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1992 Fleetwood S&S Hearse, 1993 Buick Roadmaster
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Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

Make a video, put it on youtube, and link it here. I dunno of any other way.
 

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2006 STS-V
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Discussion Starter #11
Re: Loud Short sqeal sound on cold start-up - NOT THE BELT!!!

I managed to get a good recording of it on my phone, but I'm not sure how to get it onto here. In the advanced area of where these threads can be written, it allows for all sorts of attachments other than audio clips. If anyone knows how to do this other than me making an actual video, please let me know. Or, if anyone would like to hear the clip, feel free to send me an email address of where you'd like it to be sent. Thx
 

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Discussion Starter #13
Well, I made an audio clip which couldn't be posted to this site, so I videoed the audio, and when I just went to attach it, the file was "too large to process". I give up.
 

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98 DeVille, 97 DeVille d'Elegance
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Post to an image site like flickr or to youtube and post the link to it. Only way around it as Available space on this site is very small.
 

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2003 DTS
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Have you started the car without the serp belt on? It would take you five min to verify that the nose is absolutely not the belt or anything belt driven. If it's not the belt, my money would be on your starter.
 

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White Diamond '03 DHS (with DTS floor shift)
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:noidea: hard to place that sound, but I would agree with reppinshadyvill.
 

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2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
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26,323 Posts
That sounds like a sonar blip.

To me, it doesn't sound like a metallic screech or a rubber squeal, it's too low in tone. Long shot, but there's not an aftermarket alarm siren in there, is there?
 

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2006 STS-V
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Discussion Starter #19
Thanks, but I wouldn't be adamant about pointing out that its a) not the belt, b) that its coming from the opposite side of the engine, and c) that it makes the same distinct sound when slamming on the brakes and going into a skid, if I thought that there was a remote chance that it was belt related. That said, I agree that it wont hurt to disconnect it to confirm that its not belt related. And no MC, I don't have an aftermarket alarm system or siren :) Lol, a sonar blip... I wonder.....
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Sounds like a serp belt squeal as the alternator turns on after start. Stops after 4 - 8 successive starts because the belt heats up and grabs a little better ????????
 
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