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FEATURES
GEN
INFO
10
Fuel injector
11
O
2
sensor
12
Catalytic converter
13
Crankshaft position
sensor
14
Coolant temperature
sensor
15
Spark plug
16
Cylinder identification
sensor
17
Pressure regulator
18
Battery
19
ECU
20
Atmospheric pressure
sensor
21
Fuel injection system
relay
22
Engine trouble warn-
ing light
23
Lean angle cut-off
switch
24
Air cut-off valve
25
Fast idle plunger
26
Adjustable air intake
duct
27
Intake solenoid
1
Ignition coil
2
Air filter case
3
Intake air temperature
sensor
4
Fuel delivery hose
5
Fuel tank
6
Fuel pump
7
Fuel return hose
8
Intake air pressure
sensor
9
Throttle position sen-
sor
FEATURES
OUTLINE
The main function of a fuel supply system is to provide fuel to the combustion chamber at the optimum
air-fuel ratio in accordance with the engine operating conditions and the atmospheric temperature.
In the conventional carburetor system, the air-fuel ratio of the mixture that is supplied to the combustion
chamber is created by the volume of the intake air and the fuel that is metered by the jet that is used in
the respective chamber.
Despite the same volume of intake air, the fuel volume requirement varies by the engine operating
conditions, such as acceleration, deceleration, or operating under a heavy load. Carburetors that me-
ter the fuel through the use of jets have been provided with various auxiliary devices, so that an opti-
mum air-fuel ratio can be achieved to accommodate the constant changes in the operating conditions
of the engine.
As the requirements for the engine to deliver more performance and cleaner exhaust gases increase, it
becomes necessary to control the air-fuel ratio in a more precise and finely tuned manner. To accom-
modate this need, this model has adopted an electronically controlled fuel injection (FI) system, in
place of the conventional carburetor system. This system can achieve an optimum air-fuel ratio re-
quired by the engine at all times by using a microprocessor that regulates the fuel injection volume
according to the engine operating conditions detected by various sensors.
The adoption of the FI system has resulted in a highly precise fuel supply, improved engine response,
better fuel economy, and reduced exhaust emissions. Furthermore, the air induction system (AI sys-
tem) has been placed under computer control together with the FI system in order to realize cleaner
exhaust gases.