there is a kind of metal grinding noise coming from under my car it is hard to explain but goes away when i hit the brakes. That's the best way i can describe it i don't know if anyone knows what it could be

 

What type of car do you have? Do you mean it goes away when you are stopped? Any more description of it? More info and we could help you out better.

 

you said it goes away when you hit the brakes, meaning when you're not giving it gas? is the sound there when the car is idling?

 

exhaust heat shield.

 

Or something metal loose.

 

Check your brake pads. My car did the same thing. When I gas, there would be a screeching noise, like metal on metal. Then when I braked, it went away. I changed my brake pads and now there's no noise.

 

my rotars had rust around the edges and when my car moved it rubed on the shield thing there and made a metal sound...u might wanna check that

 

Yea, the brakes could be going bad too.

 

i had this problem on another car. it was the catalytic converter. same exact thing. when i brake it went away. easy and cheap fix. hope that'll help.

 

my money is on brake pads. Civic pads have a little metal piece that will make contact with the rotor and make annoying noise to let you know you need to replace your brakes. put it up on a jack and take your wheel off all itll take is a look to see if thats the problem.