Oxygen Sensor Check - Mitsubishi MOTORS Space Runner 1999 Workshop Manual Supplement

Equipment side
Oxygen sensor
connector
(front)
MB991223
MB991223
MPI –
On-vehicle Service

OXYGEN SENSOR CHECK

<Oxygen sensor (front)>
1. Disconnect the oxygen sensor connector and connect the
special tool (test harness) to the connector on the oxygen
sensor side.
2. Make sure that there is continuity (2.5 – 5.0 Ω at 20 C)
between terminal 3 and terminal 4 on the oxygen sensor
connector.
3. If there is no continuity, replace the oxygen sensor.
4. Warm up the engine until engine coolant is 80 C or higher.
5. Use the jumper wire to connect terminal 3 of the oxygen
sensor connector to the battery (+) terminal and terminal
4 to the battery (–) terminal.
Caution
Be very careful when connectiong the jumper wire;
incorrect connection can damage the oxygen sensor.
6. Connect a digital voltage meter between terminal 1 and
terminal 2.
7. While repeatedly racing the engine, measure the oxygen
sensor output voltage.
Standard value:
Engine
When
racing the
engine
8. If the sensor is defective, replace the oxygen sensor.
NOTE
For removal and installation of the oxygen sensor, refer
to GROUP 15 – Exhaust Pipe and Main Muffler.
Oxygen sensor Remarks
output voltage
0.6 – 1.0 V If you mark the air/fuel ratio
rich by racing the engine
repeatedly, a normal oxygen
sensor will output a voltage of
0.6 – 1.0 V.
13B-73
13100510222