I've owned a 2008 Chevy Impala for about 7 months. It's at about 115,000 miles. It runs great...haven't had any problems out of it. So far. But there are a few things that concern me.
When I start the car, I hear this squeaking noise under the hood. I do not always hear this---it seems as if it may be tied with cold weather, like it's something that only occurs in the morning. But regardless, it seems abnormal. It subsides after a few minutes. The other thing I am noticing is that normally within the first 10 or 15 minutes of operation, if the car is at a stop light I'll hear some strange humming accompanied by vibrations. Sometimes the lights will flash faintly when this happens.
When I first purchased the car, I had a mechanic check it out. The engine, transmission, radiator, etc. were in excellent condition. I'm hoping that this is not anything serious, but I figure these are still sounds that I should not be hearing with a car in good condition. Any advice would be greatly appreciated.