So yesterday I was eating Torchy's in Dallas and when I got back to the car and fired it up, discovered something that worried me a little bit. I started my car and was waiting for my passenger to get in. He knows a lot about cars too, as he has mod'ed his MS6 and is a big car fanatic. Upon walking to the car I guess he heard a sound that he wanted to investigate, so I popped my hood.
Apparently, when I rev the engine the rev peaks (it can be as high as 6k RPM or as low as 3k rpm, it just is any rev) and as the revs come back down there is a rattle. We actually took a video that I put on YouTube.
Let me first say that if you listen to this on your phone you MAY not hear the rattle. I can barely hear it and I know others had a hard time hearing it. If on a computer you'll need the volume up or headphones on. After uploading to YouTube I put on some headphones on my computer and it was pretty clear.
The rattle starts around 2-3 seconds, again around 4-5 seconds, again around 9-10, and once more around 16-17 seconds. Each time you'll notice I rev my engine a bit first, and it is as the revs are coming down. This happens consistently, and within the car you can't hear anything.
This may be normal, or something, but I have never noticed before so I just want to be safe.