Every time I start my car, I hear this rattling noise under my hood. Im not sure what it is, I change my oil regularly, and I take generally good care of my Civic. I have a 94 EX Coupe. Maybe some of the exhaust piping came loose?

 

ok, your description is a bit vague. is the noise coming from under the hood or under the car? start the car, like normal, and open the hood, listen for where it's coming from and try to describe what it sounds like.

 

well, when I started my car up this morning. It was under the hood (like the engine bay) not the car... Like, when the car is running the engine shakes a little bit... It sounds like a loose pipe, but Im not sure.

 

bump

 

get under the car when its cool and shake up the pipes, you can ususally hear where its rattleing. Or you can lightly tap them with a rubber mallet. Quite common for the sheilding to rust out and start to rattle.

 

when ur warming up ur car look right under the car where the cat is, its probably ur cat, mine makes the same noise

 

That can be way to many things, and you will never find the answer on the internet. Just take it to a shop and get them to check it out.