Fuel Injection Control - Suzuki F6A Service Manual

FUEL INJECTION CONTROL

A speed density method is used whereby ECM calculates the air intake amount according to the engine rpm (crank
angle sensor) and intake manifold pressure (pressure sensor), and determines the basic injection time. The fuel
injection method (timing) and fuel injection amount (time) are controlled as follows using a start mode that is used when
starting the engine and a feedback mode that is used during normal driving.
CRANK ANGLE
SENSOR
PRESSURE SENSOR
THROTTLE
POSITION
SENSOR
WATER TEMP
SENSOR
VEHICLE
SPEED SENSOR
TRAVELING
RANGE
SIGNAL
O SENSOR
2
BATTERY
VOLTAGE
STOP MODE:
Engine speed under 50 rpm (when input of crank angle sensor signal is 0.8 sec or more)
START MODE:
In the fuel injection mode used outside of stop mode, when the engine speed is 600 rpm or lower, injection is performed
simultaneously for all cylinders upon each crank angle sensor signal input. However, when the temperature is extremely
low, multi–division injection is used. Fuel injection amount determined by adding a correction for ineffective injection
time to the following starting injection time.
S
Starting injection time: Time determined according to cooling water temperature. As the injection time is extended
the lower the cooling water temperature becomes, and starting ability is increased.
S
Ineffective injection time: in order to correct for delay in the injection time due to low battery voltage, the charging
time to the injectors is extended according to the degree of reduction in battery voltage.
ENGINE RPM
MANIFOLD PRESSURE
THROTTLE OPENING DEGREE
COOLING WATER TEMPERATURE
VEHICLE SPEED
DURING D, 2, L OR R RANGE SHIFT
MIXED GAS LEACH LINE
BATTERY VOLTAGE
ECM
BASIC
INJECTION
INJECTION
TIME TIME
CORRECTION
INJECTOR
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