Outline
The Miller cycle engine is a high-efficiency engine which achieves high fuel economy performance by obtaining a high-expansion ratio.
The Miller cycle engine achieves a high-expansion ratio without increasing its effective compression ratio by retarding the intake air valve close timing.
Operation
1. Intake air is introduced into the cylinder.
2. The intake valve is kept open after the intake stroke is finished to force the air in the cylinder to flow back to the intake pipe.
3. The compression stroke starts from the position in which the intake valve is closed (small compression).
4. The air-fuel mixture is combusted and the piston is pushed down to BDC (large expansion).

Mechanical
Non Return Valve InspectionPCM
Purpose/Function
High-level driveability and lower fuel consumption have been realized by
controlling the appropriate engine conditions (fuel injection/ignition timing)
according to operation conditions.
Controls each output part based on the signal from each input part.
...
Valve, Valve Spring, Valve Seal, Valve Guide
Purpose, Function
Valve
The intake valve is pressed down by the cam, the intake air passage is opened,
and air is introduced into the cylinder.
The exhaust valve is pressed down by the cam, the exhaust air passage is
opened, and combustion gas is exhausted from the cylinder.
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Reporting Safety Defects (U.S.A.)
If you believe that your vehicle has a defect which could cause a crash or could
cause injury or death, you should immediately inform the National Highway Traffic
Safety Administration (NHTSA) in addition to notifying Mazda Motor Corporation (Your
Mazda Importer/Distributor).
If NHTSA receive ...