Rep Power: 0

I had all four tires replaced and two ball joints also. After got car back from mechanic a weird sound from engine bay after car has been driven for over 15 minutes. No codes thrown out but when accelerate it sounds like a metal can vibrating/or like baseball cards in spokes. It also does it when in neutral and you give it a little gas. It didn't start this till after I got it back from mechanic after ball joints replaced.

Not sure if info helps but got belts replaced in January. Car has 148k miles. Thanks!

 
Rep Power: 211

probably a loose heat shield on your exhaust or cat vibrating

 
Rep Power: 245

Have someone press the gas pedal while you look around the engine bay for the source of the noise.

Or have the shop look for it.

Probably a heat shield like mikey said.