Hello, I own a 91 miata with a BEGI system 3 turbo. I have been getting a
rattleing recently that starts at 2.2k RPM’s and stops at 2.5k RPM’s. It
does it even when i am in neutral. I thought it would be one of the bolts on
the heat shield over the turbo, but it isn’t. I am using 91 octane fuel, and
10W-30 synthetic oil.

here is a video clip of what it does… 5.7MB

http://myweb.cableone.net/shannonv/carrattle1.mpg

-levi