I own a 2006 M35x that has a musty swampy smell every time I have started the car this summer. It goes away after 15+ seconds. It also is not present if I shut the car off and then restart it in an hour or so. Has anyone else experienced this?
Common problem on cars that are used in recirc mode. You can buy cleaner at just about any auto parts store and run thur the air circ system. Intake is under the hood just below the wipers.