Yamaha FZ8NA Service Manual

Also see for Fazer FZ8-SA: Owner's manual Owner's manual Owner's manual

FEATURES1-4EAS39P1102FI SYSTEMThe fuel pump delivers fuel to the fuel injector via the fuel filter. The pressure regulator maintains thefuel pressure that is applied to the fuel injector at only 324 kPa (3.24 kgf/cm², 46.1 psi). Accordingly,when the energizing signal from the ECU energizes the fuel injector, the fuel passage opens, caus-ing 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 greaterthe volume of fuel that is supplied. Conversely, the shorter the length of time the fuel injector is ener-gized (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 fromthe throttle position sensor, sub-throttle position sensor, crankshaft position sensor, intake air pres-sure sensor, atmospheric pressure sensor, intake air temperature sensor, coolant temperature sen-sor, speed sensor and O 2 sensor enable the ECU to determine the injection duration. The injectiontiming is determined through the signals from the crankshaft position sensor. As a result, the volumeof fuel that is required by the engine can be supplied at all times in accordance with the driving con-ditions.Illustration is for reference only.1. Fuel pump2. Fuel injector3. Ignition coil4. ECU (engine control unit)5. Intake air temperature sensor6. Speed sensor7. Throttle position sensor8. Atmospheric pressure sensor9. O 2 sensor10.Catalytic converter11.Coolant temperature sensor12.Crankshaft position sensor13.Intake air pressure sensor14.Throttle body15.Sub-throttle position sensor16.Air filter caseA. Fuel systemB. Air systemC. Control system