Get someone to help you and start tracking down exactly where the rattle is at. I had a rattle annoying me. I found that it was the passenger seat belt. I solved it by buckling the seatbelt, but when it warms up, I plan on looking at better solutions.
2013 MCA Edition-Sterling Grey
Roush body kit - Splitters/hood scoop
Whiteline suspension w/Koni shocks