Diagnostic Method

Detect the trouble by calculating the time from the completion of the fuel cut to the beginning of the rear oxygen sensor voltage starting to rise.

Fig 1: Rear Oxygen Sensor Voltage Graph

Courtesy of SUBARU OF AMERICA, INC.

Judge as NG when the following conditions are established.

JUDGMENT VALUE SPECIFICATION

Malfunction Criteria

Threshold Value

Output voltage value of rear oxygen sensor

< 0.2 V

Elapsed time⁽¹⁾

> MAP

⁽¹⁾	Elapsed time: The time since the λ became less than 1 after the end of fuel cut

MAP SPECIFICATION

Intake air amount (g/s)	15	17	18	20
Elapsed time (s)	7.0	5.5	5.0	5.0

Time Needed for Diagnosis: Less than 1 s

Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.