i hear this rattling noise underneth my car i'll stop when i acclerate but the noise comes back when i stop or turn a corner. i think that the noise is coming from the exhaust pipe. it sounds like rattling metal.

 

Heatshield probly.

 

whats the name part of the exhaust that goes directly underneth the car?

 

Catalytic converter?

 

i'v looked under the car and i find that the pipe that goes from the engine to about the back of the car has holes on it. i don't know exactly that part is called. does anyone know what i'm talking about? i want to try to buy the part online but i don't know the name of that exact part of the exhaust.
i looked at the catalytic converter and that wasn't it.

 

Might be cheaper to take it to a muffler shop and let them replace the pipe for ya.