One problem related to engine squeaking noise 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.
Squeaking noise from engine compartment. Source appears to be engine mount#4. Needs to be replaced and greased. Noise occurs in motion, no correlation with turning or speed.