So since the temperatures started dipping under 35 degrees this season, the Equinox has had a high pitched squealing/squeaking sound when starting up in the morning. It typically lasts for about a minute then goes away as the car warms up.
This is the first time this sound has come up. Last winter and the winter before this had never been an issue. I had the engine repaired in warranty about 20K miles ago, with the #6 injector as well as the high and low pressure fuel pumps being replaced. The car is run with 87 octane and has had oil changes done every 5K with Valvoline Synpower 5W-30.
What the hell could it be?