Yamaha 2002 TDM900, Service Manual

Page: 28 / 475

1-17
FEATURES
GEN
INFO
1
Ignition coil
2
Injector
3
Intake air temperature
sensor
4
Intake solenoid
5
Throttle position
sensor
6
Intake air pressure
sensor
7
Crankshaft position
sensor
8
O
2
sensor
9
Coolant temperature
sensor
10
Cylinder identification
sensor
11
Spark plug
12
ECU
13
Igniter
14
Atmospheric pressure
sensor
15
Catalytic converter
THREE-WAY CATALYTIC CONVERTER SYSTEM
System outline
This is a highly efficient exhaust gas cleaning system that effects air-fuel control through a joint effort by
the FI system, O
2
sensor, and the three-way catalytic converter system. By effecting comprehensive
control of the air-fuel ratio in this manner, this system reduces the CO, HC, and NOx in the exhaust
gases.
The FI system controls the mixture to an optimal air-fuel ratio (basic air-fuel ratio) that matches the
operating condition of the engine in order to realize an ideal combustion.
Furthermore, an O
2
sensor that detects the concentration of oxygen that remains in the exhaust gas is
provided in the exhaust pipe for the purpose of maximizing the performance of the three-way catalytic
converter and to clean the exhaust gas at a high degree of efficiency. Based on this data, the ECU
applies more precise compensation to the basic air-fuel ratio, in order to maintain the mixture in the
vicinity of the stoichiometric air-fuel ratio of 14.7 : 1.
Through the joint effort of these control systems, the exhaust gas is cleaned in a highly efficient manner
without sacrificing engine performance.
Three-way catalytic converter system diagram