For about 6 months now I’ve been experiencing a BMW X3 muffler rattle. At first I ignored it but as it became more persistent and embarrassing, I decided to get under the car and troubleshoot it. All the connections under the car were firm and in good condition. What was causing the muffler rattle that sort of sounded like an aluminum can in my exhaust? I also noted, it only seemed to happen on start up, idle, and when the car was under no load decelerating.
I took a video and pasted it below with more details. Basically, there is a baffle in the right exhaust pipe that opens and closes based on a vacuum line. At idle and no load, the baffle closes and it opens once the engine starts winding up. It’s also closed when the car is off...
Read More