I guess you have the 2.5 since you said muffler and not muffler's. If you had an exhaust leak it would most likely be closer to the engine to have you smell it. I would check the mid pipe and flex pipe area and flanges in this area. You would have to get underneath the car with it running to check, if you can't safely do this then I would take it to a exhaust shop to have a look.I am smelling the exhaust coming into the car. Is there a vent closure in the engine compartment? I checked the muffler and did not see any holes etc..