I’ve got a 2012 California that is due for its 20k service that has developed a rattling metallic sound from underneath somewhere every time it’s been run warm and passes 1600 RPM. No noise at all at any other RPMs. No noise when revving past that RPM in neutral. Does anyone have any idea of what could be causing the rattle? I’m thinking a lose heat shield for the exhaust would make noise at other RPMs too?!