Hi there. We love our 2006 300C but the rattle from under the passenger side is driving us crazy. I can reach up under the car from just behind the front tire and replicate the sound when I tap on this tin shield thing. It looks like it might be covering some brake lines? It runs just outboard of the exhaust, starting under the hood near the back corner of engine and follows those small lines down and back. It stops under the passenger foot well area. What is it guarding and can anyone recommend a way to stop it from rattling? Any help is appreciated. I'll check back after work tomorrow. Thank you in advance.