I have a supercharged Cobalt SS, I have been having a problem with the belt squeaking
It only squeaks once the motor is up to temp
when I first start it there is no squeak and it does not go away until I shut the car off
I tried the old bar of soap trick and it works for maybe a minute and the squeak is back
Anybody know what this could be?

 

Possibly your tensioner pulley?

 

New belt imo

 

Yea im going to try getting a new belt
even though this one is in great shape
hopefully this works!!!
If anyone else has had this problem, and got it fixed, let me know!

 

Just went through this EXACT same thing. Replaced the tensioner, still squealed, replaced the belt with a new GMS2 one thinking it was worn out (I'm on a 2.8" pulley). The squealing stopped for about a week then came back. What stopped it was using the stock belt with oversized tensioner. But something that's the easiest is take the belt and flip it the other way. That worked for me too.

 

i'm having a squeak thats only there when the car starts and its there for maybe 2-5 minutes usually or if the cars warm it goes away.

i replaced my tensioner pulley (helped a ton but PITA to install) but now i'm thinking its the idler pulley (one behind tensioner pulley) buuut this isn't your same situation i think goood luck

 

It's the belt.