loud vibration on 2008 Honda Civic

When I first start my car their is a loud vibrating noise under the hood, sounds like an part of the exhaust, maybe a heat sheild or something. It goes away after driving for a while and every thing heats up, any ideas ?

Asked by for the 2008 Honda Civic
Its hard to speculate what a noise could be without being able to hear the noise first hand. It could quite possibly be a cracked or warped exhaust manifold that indeed as it warms up could cause the noise to go away. Best to get it checked out.
1 more answer , 2 more comments
I HAVE THE EXACT SAME PROBLEM!!!! Have you had any luck discovering the culprit???
Yes it was the motor mount on the passenger side. I replaced it myself.
is it costly to change the motor it gear mount or the engine mount.....