Hey all...
Just bought my new Mazda 3 but am wondering if a noise in the muffler when starting is normal.....I've never heard it on any other type of car....
Do you mean inside the muffler canister itself? Possible a manufacturing defect left a piece in there not spot welded. Or could just be the heat shield or other part of the exhaust that vibrates or is slightly contacting something. You might try peering under the car while someone else starts it to help pinpoint the location.