Mazda 2009 RX-8, Особенности сервиса

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CONTROL SYSTEM [13B-MSP]
01-40–17
01-40
Fuel Injection Distribution Control
x
There are primary, secondary injectors, and they
independently control fuel injection amount and
timing according to the amount of fuel demand
from the engine.
x
The amount of fuel demand from the engine is
determined by each correction of the charging
efficiency and injection time after engine start.
x
When the amount of fuel demand from the engine
is low, only the primary injectors inject fuel. When
the amount of fuel demand from the engine
increases, fuel injection in the order of secondary
injector begin injection.
Synchronized Injection Control
x
The synchronized injection control performs fuel injection according to each timing that has been determined
by the intake stroke of the rotors.
x
The synchronized injection control includes fuel injection control at engine start and fuel injection control after
engine start. Synchronized injection control performs fuel injection based on injection time (final injection pulse
width) and fuel injection timing demanded by each rotor.
Injection time at start
x
Calculated by adding the engine speed correction to the basic injection time at engine start, the throttle valve
opening angle correction, and the volume decrease correction at engine start, and then the final injection pulse
width is calculated by adding the ineffective injection time to the injection time at engine start.
x
Basic injection time at engine start is determined based on ECT and shortens as the ECT increases.
x
Ineffective injection time is determined according to battery voltage and lengthens as battery voltage becomes
lower.
Injection time after engine start
x
The injection time after engine start is calculated from the charging efficiency, ineffective injection time and
each type of correction.
Charging efficiency
—
The charging efficiency is the ratio of intake air amount that is actually taken in relation to the maximum air
charging amount (mass) of the operation chamber. This value becomes larger in proportion to the increase
in engine load.
Ineffective injection time
—
Ineffective injection time at engine start is determined according to the battery voltage and lengthens as the
battery voltage becomes lower.
PRIMARY INJECTOR
ENGINE DEMAND
FUEL VOLUME
LOW HIGH
EFFECTIVE INJECTION PULSE
SMALL
LARGE
SECONDARY INJECTOR
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Correction Condition Amount of Correction
Engine speed correction Determines correction amount based on
engine speed.
x
Correction amount lengthens as the engine
speed increases.
Throttle valve opening angle
correction
Determines correction amount based on
throttle valve opening angle.
x
Correction amount shortens as the throttle
valve opening angle increases.
Volume decrease correction
at engine start
Determines correction amount based on ECT
and engine speed at engine start.
x
After starter is on for approx. 1 s and any
one of the following conditions are met,
injection time gradually decreases:
—
ECT at fixed value or more
—
Engine speed at target engine speed or
more
—
Approx. 30 s of cranking time elapsed