Squealing sound on cold starts, 2010 Equinox 3.0L.

[mrDenali]

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?

[MrCritical]

does it matter if the hvac system is on or off?

[Tone]

Sound a lot like a slipping belt. It's a pretty horrible and loud sound -- I've experienced it. Usually an indication of worn belts that need replacing. It should be a relatively inexpensive fix. That said, I'm a little surprised that the belts wore that quickly -- do you have high miles?

[Tomko]

Slipping belt on the alternator. Starting the car drains battery power, so the alternator load is high during the first minute or so while charge is returned to the battery.

It could also be that there is coolant or other contamination on the belt causing the slip.

It's a horrible analogy to make - but when slipping, Dynagroove belts sound like a cat that's being skinned alive. Not that I've ever heard, or ever want to hear, what that truly sounds like.

[mrDenali]

It only happens if the car has sat in the cold overnight. And it doesn't sound at all like a belt.

Im at 43k miles.

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[1999 White C5 Coupe]

It only happens if the car has sat in the cold overnight. And it doesn't sound at all like a belt.

Im at 43k miles.

Sent from Jo Momma using AutoGuide.Com Free App

Sounds like a defective idler pulley (one or more). As the pulley bearing heats-up, it will quiet down. Eventually, it will wear-out and seize-up. I have changed them on other GM cars/engines - but not the 3.0 Equinox. Most are fastened to the engine with a single 15 mm bolt.

Good luck.