Hi, I love my Fusion (2010) but have had the same rattling noise from the passenger seat. My dealership has had a really hard time with the car as it has presented a number of challenges (rear window motors had to be replaced). The passenger seat frame turned out to be broken so they had to replace the seat (and did scratch all the panels up really bad when replacing them), then the problem with the airbag light--they reprogrammed the unit a few times then after talking with a Ford Engineer found that the module had to be replaced. The latest is that when they replace the seat track it is required that a small clip be replaced--they didn't know about this so have ordered that part. I'm hoping that this will end the multiple issues....although my transmission keeps slipping when it's cold out. I guess that will be the next problem. Good luck! My noise is better though.
