[SuperSound]

Originally Posted by seanblurr

Forgive me as I am not a Zl1 owner and just stumbled across this thread, but what exactly does pulling the fuse do? I'm fairly certain if you leave the exhaust in "track" mode it will stay open regardless of driving conditions... I understand that the valves apparently close at freeway speeds, regardless of exhaust mode, but this car leaves quite a bit of carbon build up on the exhaust tips, and my inners are pristine, as if no air has flowed out. Maybe I just don't drive long enough at a steady freeway speed

It's not only at highway speed, it's at light throttle positions as well. It makes a bigger difference on A8 cars than M6 ones. Exhaust is coming out both pipes, but the soot buildup is always worse on the bypass valves because the muffler is not hiding it. Try putting yours in Stealth and cold crank it. Watch all the crap that comes out the inner pipes then. Guys running the fuse pull need to reinstall it periodically to blow out the muffler/inner pipes. One of the reasons I got a M2W controller so I can do it with a remote.