Fl System - Yamaha FZ09E Service Manual

FEATURES
EA$1AC1 1Q2
Fl SYSTEM
The fuel pump delivers fuel to the fuel injector via the fuel filter. The pressure regulator maintains the
fuel pressure that is applied to the fuel injector at a certain level. Accordingly, when the energizing signal
from the ECU energizes the fuel injector, the fuel passage opens, causing the fuel to be injected into
the intake manifold only during the time the passage remain open.
Therefore, the longer the length of time the fuel injector is energized (injection duration), the greater the
volume of fuel that is supplied. Conversely, the shorter the length of time the fuel injector is energized
(injection duration), the lesser the volume 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, accelerator position sensor, coolant temperature sensor, lean angle sensor,
crankshaft position sensor, intake air pressure sensor, intake air temperature sensor, speed sensor and
0 2 sensor enable the ECU to determine the injection duration. The injection timing is determined
through the signals from the crankshaft position sensor. As a result, the volume 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 .
1
A
#1 #2 #3
15
1. Fuel pump
2. Injector
3. ECU (engine control unit)
4. Throttle position sensor
5. Accelerator position sensor
6. Speed sensor
7. Lean angle sensor
8. Intake air temperature sensor
9.
0
2 sensor
10.Catalytic converter
B
14!
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•'
13
1-3
11
9
12
11 . Coolant temperature sensor
12.Crankshaft position sensor
13.lntake air pressure sensor
14. Throttle body
15.Air filter case
16. Throttle servo motor
A. Fuel system
B. Air system
C. Control system