get a squeal or whistle when excelerating only in temp below 30 degrees
A squeal could be from a cold belt. A whistle could be a vacuum hose leak.
look at your fan belt and fan belt bracket something could shrink a little with the cold causing the looseness and noise.
Check the easiest first. Being 9 years old, the idler pulley could be going bad.... Take the belt off the tensioner only. Makes reinstalling it a lot easier. Check the idler pulley by simply moveing it up and down and back and forth. If there is play there, it's bad. Cost maybe ten bucks. May not be what is making the noise, but it is obvious something with a bearing and a seal has gone bad.
It's a good idea to change it anyway. I've changed many over the years for the neighbors. Usually after the thing goes totally bad and flies apart, destroying the belt in the process and requiring a tow home. All the neighbors said the same thing. That is was making a "kinda squeeking noise" at times, at times - for a while. Then it all of a sudden starting seueeking real loud, I heard a bang and the engine killed.
Thanks,idler pulley was replaced with new belt last year,thinking it could be an alternator bearing?this high pitched squeal only when outside temp below 30 and will squeal at around 70 mph /2500 rpm going down highway
Try having some slightly race the engine while in park. (an adult please) The squeel should occur if it is in the engine. Other possible causes are the water pump, powerstering pump, A/C, and any other belt driven accessory. It could also be a bearing going bad where it causes the belt to slip across the pulley. Good luck.
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