I’m working on my 02 4Runner currently. On cold starts there is a loud squeal coming from the engine, and it gets worse with dropping temps outside. Eventually it will go away, but it’s staying around longer and longer now that’s it’s getting colder so I would like it fixed. I noticed that when the squealing happens while it’s idling after I turned it on that the headlights would dim with the squealing, then go back to normal when it stopped, repeat until the squeal completely left. Under the hood it sort of sounds like it’s coming from the alternator. Can an alternator squeal like that and then go away? I thought maybe the belts were loose but they all seem to be the correct tension. Could it be a fan clutch? It seems to be more present driving from my house to the highway where the fan wouldn’t be engaged