ENGINE CONTROL SYSTEM 3-35
O
2
FEEDBACK SYSTEM
After extended usage, the engine components may become deteriorated or worn out.
This might make the A/F (air / fuel mixture ratio) incorrect which could affect exhaust emissions. To correct
the A/F, an O
2
sensor must be temporally installed in the exhaust manifold. This sensor is used to measure
the concentration of oxygen in the exhaust gas at engine speed of 2000, 3000 and 4000 r/min.
The ECM uses the input data from the O
2
sensor to correct the compensation coefficient of the fuel injection
duration map within the ECM itself.
NOTE:
See the “FUEL MIXTURE CHECK (O
2
FEEDBACK)” section on the page 2-21 for the procedure of the O
2
feedback operation.
O
2
sensor:
Informs ECM of concentration of oxygen in exhaust gas.
ECM
Feedback