I just finished a faulty evap repair on a Mazda 3. I'd like to share the experience.
2008 Model Year, Mazda3, manual, 2.3L engine.
Check engine lamp, read codes P0442 (Evaporative Emission Small Leak) and P0455 (Evap Emission Large Leak)
Read up on line. Most likely source is fuel cap, followed by engine compartment mounted purge valve.
Test purge ...