One problem related to engine exhaust system has been reported for the 2012 Mazda MAZDA3. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2012 Mazda MAZDA3 based on all problems reported for the 2012 MAZDA3.
There is a rotten egg smell coming from the exhaust pipe from the car. Mazda dealer is unable to resolve the problem when I went back for service. I change gas to shell as recommended by the dealer, and the problem persists. Dealer said that this is comon problem and blamed it on the gasoline blend.