Helio, new here. I have a 2012 Chevy Tahoe and lately upon starting it after sitting for long periods (overnight or while at work) I'll hear a growing/humming sound from the front two times, then a few seconds later the cooling fan will kick on. Fan will stay on most of the drive, will stop at times but kicks back on until I turn my Tahoe off. Any idea what the noise is coming from and why the fan would kick on? I've also had three fan luck on after starting it but the growing/ humming noise wasn't there after starting it. Feel like my temp sensor is bad causing the fan to kick on super early, but the noise and fan combined have me puzzled and concerned. Any help is greatly appreciated. Thanks