My 2007 Cobalt just started making a popping noise from the front end. I only hear it when I come to a stop and quickly release the brakes. If I release the brakes slowly, it won't make the noise at all. So I'm guessing the problem might be that the brakes are sticking in the front? When I'm driving slowly, like 20-30 mph and apply and release the brakes quickly, I don't hear the noise. I changed the rotors and pads about 15,000 miles ago and I did use grease in the areas where the pads slide and also on the pins. Should I take the calipers apart to check and regrease everything?

 

Does sounds like it could be brakes sticking, but it shouldn't matter how you release the pedal, it should make the noise. When I had a stuck front caliper on my Cavalier it made the sound not matter what, it wasn't always as noisy as the rear but it was there. I would also think you'd notice it either in smell or heat after a decent amount of driving OR in abnormal pad wear depending on how long it's been going on.

COULD be suspension as well. The stock end links and CABs aren't the greatest. BUT, you'd hear the noise on a hard accel as well.

 

I had this at about 25k and the dealer installed new control arm bushings under warrantee.
Then it started doing it again at about 50k. It also rattled over bumps. This time it was a sway bar link on the passenger side. I'm having brain fade at the moment but I think thier the sway bar control links. I replaced both sides with ones that are greasable.

Grab the sway bar at the end near the wheel and shake it up/down and see if it rattles.