Vibrations from underneath

Hey all;
Out of nowhere the other day, there started a rattle coming from under the car. I turns out that the heat shield on the underside of the car where the exhaust runs decided to start rubbing up against the cat-back. IDK how this happened. It has not made a sound ever! Now all of a sudden, the heat shield vibrates off the flange connecting the first pipe to the second pipe at the bend in the center of the car.

I tried bending the shield back, it's hard, but I got it shaped so the flange isn't hitting at all. Only had a slight rattle at WOT at 3k rpm. Then, coming home, it was doing it badly again. Any ideas on how to stop this? It sucks because it rattles the most at idle. I'll be at a light and you hear boom boom boom rattle. So annoying. Any ideas on how to stop it? I'm going to try rebending again later.

Is there a support or mount or something broken on it, letting it come down and touch the exhaust? That would be my best guess. BTW, do you still need that TPS? I completely forgot about it until about 5 minutes ago.

I've checked. It was fine. Everythings still secure.

Yes I still do. I actually thought it earlier today. Got the logger to read 5% at idle now and 78% WOT!! Let me know if you got any? How about a knock sensor too?

I'm going out their tomorrow to work on one of the Eclipses, I'm actually making a note as I'm typing so I'll remember to look. As for your exhaust sound, I have NO idea if everything is still in place and tight.