Hey guys not too long ago i just came back from a trip. I noticed that my engine has a rattling noise when i accelerate. It usually happens when i get up to 3k rpm you can really hear it rattle. When i turn on the car and just let it run you can hear it as well. At first i thought it was just my cover sheet underneath the car that was loose, but after tightening all the screws it still made the noise. Any idea what this could be? I plan on taking it to the shop but just wanted to get a few ideas from you guys. Thanks!