I have 97 Civic, and it made rattling noise from the bottom, and I found out that it's the heat shield thingy at the bottom by the muffler.
It was all rusty and stuff so I kinda had to take it out because it wouldn't unscrew, they were just falling off.
Do I have to keep that on? or is it OK to have it off?
It seems to cover the gearbox because it was right underneath of where the gear shift was.
Even if I have it off, I don't think it'll affect anything because that part is well ventilated.
Anyone had the same problem? Let me know your imputs!

 

i have no heat sheilds on my car.... just extra weight. drove 50k that way with no problems. keep it off at your own risk. i had good luck so far.