Lancer L4-2.0L SOHC (2004)
2. While repeatedly revving the engine, measure the heated oxygen sensor output voltage.
CAUTION:
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Be very careful when connecting the jumper wire; incorrect connection can damage the heated oxygen sensor.
-
Be careful the heater is broken when voltage of beyond 12 volts is applied to the heated oxygen sensor heater.
NOTE: If the sufficiently high temperature [of approximate 400 °C (752 °F) or more] is not reached although the heated oxygen sensor is
normal, the output voltage would be possibly low although the rich air/fuel ratio. Therefore, if the output voltage is low, use jumper wires to
connect the terminal No. 3 and the terminal No. 4 of the heated oxygen sensor with a (+) terminal and (-) terminal of 12 volts power supply
respectively, then check again.
3. If the output voltage is not within the standard value, replace the heated oxygen sensor.
NOTE: For removal and installation of the heated oxygen sensor Exhaust Manifold.
<Heated oxygen sensor (rear)>
1. Using scan tool MB991958, observe HO(2)S reading. If values are unsatisfactory, or if Scan tool is not available, use the following procedure:
1. Disconnect the heated oxygen sensor connector and connect special tool MB991658 to the connector on the heated oxygen sensor side.
2. Make sure that there is continuity [11 - 18 ohms at 20 °C (68 °F)] between terminal No. 3 and terminal No. 4 on the heated oxygen sensor
connector
3. If there is no continuity, replace the heated oxygen sensor.
4. Warm up the engine until engine coolant is 80 °C (176 °F) or higher.
5. Perform a revving for 5 minutes or more with the engine speed of 4,500 r/min.
6. Connect a digital voltage meter between terminal No. 4 and terminal No. 2.