Fi System - Yamaha FZ6-SS Service Manual

EAS00897

FI SYSTEM

The fuel pump delivers fuel to the injector via the fuel filter. The pressure regulator maintains the fuel
pressure that is applied to the injector at only 250 kPa (2.5 kg/cm
signal from the ECU energizes the injector, the fuel passage opens, causing the fuel to be injected into
the intake manifold only during the time the passage remains open. Therefore, the longer the length of
time the injector is energized (injection duration), the greater the volume of fuel that is supplied. Con-
versely, the shorter the length of time the injector is energized (injection duration), the lesser the vol-
ume of fuel that is supplied.
The injection duration and the injection timing are controlled by the ECU. Signals that are input from the
throttle position sensor, crankshaft position sensor, intake air pressure sensor, intake temperature
sensor and coolant temperature sensor enable the ECU to determine the injection duration. The injec-
tion timing is determined through the signals from the crankshaft position sensor. As a result, the vol-
ume of fuel that is required by the engine can be supplied at all times in accordance with the driving
conditions.
Illustration is for reference only.
Fuel pump
1
Pressure regulator
2
Fuel injector
3
Throttle body
4
Intake air temperature
5
sensor
Throttle position sen-
6
sor
Intake air pressure
7
sensor
ECU
8
1-3
FEATURES
2
). Accordingly, when the energizing
Coolant temperature
9
sensor
Crankshaft position
10
sensor
GEN
INFO
A Fuel system
B Control system