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!!