Carbon buildup on intake valves
Often reportedThe 2.0 SKYACTIV-G engine uses direct injection, so fuel does not clean the intake valves, leading to carbon deposits that cause power loss, rough running, and hard starting.
Engine Internal
The most frequently mentioned issue when buying a used Mazda 3 2.0 i 2014 (BM): carbon buildup on intake valves. Also, oil consumption and leaks related to the PCV system are commonly reported.
Engine varies by trim; verify the engine code on the listing.
Listed from most frequently reported, each with its source.
The 2.0 SKYACTIV-G engine uses direct injection, so fuel does not clean the intake valves, leading to carbon deposits that cause power loss, rough running, and hard starting.
Engine Internal
Some SKYACTIV-G 2.0 engine owners report increased oil consumption or localized leaks (e.g., valve cover gasket) and issues with the crankcase ventilation system (PCV valve). A clogged or faulty PCV system can increase internal pressure, leading to leaks.
Engine Internal
Owners report hesitation, minor misfires, or uneven fuel delivery that is resolved by replacing or cleaning the injectors.
Fuel System
Same trim, different year
We only publish claims we can verify. Cards come from Difetti fault records matched to this vehicle on brand, fuel, engine and generation.