"But, I'm surprised that this condition wouldn't trigger the Check Engine Light as the OČ Sensor Readings must be out of whack as well. Are you sure it's the muffler and not the Heatshield surrounding it? These use a sheet metal screw and the hole in the Heatshield can expand to the point where this sheet metal screw can no longer fasten it securely and it rattles. This type of problem usually goes away once everything heats and expands..."
I am with Jim, check the heat shield first.
__________________
Rich Belloff
|