One problem related to engine failure has been reported for the 2004 Mazda MAZDA6. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Mazda MAZDA6 based on all problems reported for the 2004 MAZDA6.
Driving on a highway from chicago to wisconsin I noticed a knock in my engine that turned into 2 thrown pistons through my engine block. I work for a crash test facility. Cars are a daily component in my life. The engine had 45,000 miles on it and Mazda rejected my warranty claim. I ended up settling with the dealership and transferring my loan to a used car. I wanted to post this occurrence of engine failure to make sure it wasn't a common occurrence.