So I just did a head gasket job on my 03 Sebring, cars started right a way and runs great, I also replaced the timing belt now when on idle there is a humming noise coming from the timing belt, it feels like the belt maybe rubbing against something, not sure. when I hit the gas peddle the noise is gone, any ideas ???

 

Did you replace the tensioner????

Try loosening the covers and see if the noise dissipates. It is very easy to misalign a plastic cover.