Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
191
2
）
Installation
Be aware of following precaution to install with steps contrarily.
■
Be aware of installation gap.
Standard: 0.5 - 1.5mm
■
Tightening torque: 7.8 - 9 N • m
VI.
Oxygen sensor
1. Component Description
Oxygen sensor is used to provide information for judging whether the oxygen in air inhaled to the fuel
in engine cylinder is excessive or not after combustion. ECU uses this quantitative information for
defined cycle control of the fuel cycle so that the three major toxic components can be mostly converted
and purified in the three-way catalytic converter.
The sensing component is a kind of porous ceramic tube; the wall is surrounded by the engine exhaust
while the inside is put through to the atmosphere. The oxygen sensor, based on concentration difference
inside and outside, calculates indirectly the fuel injection pulse width to be transmitted to ECU for
controlling of fuel injection. Simultaneously, it detects rear oxygen sensor output data and compares
with front sensors data within the ECU to monitor the working conditions of the three-way catalyst
converter.
Oxygen sensor operating voltage fluctuates between 0.1-0.9V; in 10 seconds it may change for 5-8 times;
if it is lower, indicates that the sensor is aged and need to be replaced. The sensor can not be repaired.
Fig. 4.3.014
