Accelerating from any other gear is fine, no noise. Only going from 2nd gear do I get this slight rattling noise from under the car for 2-3 seconds.

Anything I should worry about? Any ideas what it could be? 43k miles.

 

I had this problem after switching to a lower grade gasoline to save money. After switching back to super the noise went away.com

 

I only use the highest grade in my car... My car before this was a '97 Prelude, and those required Premium as well. I've never made exceptions for either. Also only use Mobil 1.

 

mine is doing this recently.

Did you find out what was the cause?