06-11-2012, 08:52 AM
Do these cars have one? I've noticed on both my M5 and my 550 that when first starting them they almost sound as if the car has a small exhaust dump somewhere to warm them up quicker. Perhaps it's the EGR valve defaulting to open that I'm hearing but engine startup is the only time it's heard. Shortly after that the car goes back to it's quiet self.