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Air Fuel Ratio (A/F) Sensor Inspection




AIR FUEL RATIO (A/F) SENSOR INSPECTION [MZI-3.7]

Sensor Output Value Inspection (A/F sensor)

1. Perform the inspection according to the following procedure using the PID/DATA monitor function. Diagnostic Monitoring Test Results

- Start the engine and warm it up.
- Drive the vehicle.
- Release the accelerator pedal while the engine speed is at 3,000 rpm or more and verify that the following monitor items fluctuate as shown in the figure while the vehicle decelerates.

- VSS
- RPM
- O2S11, O2S21





- If not within the specification, replace the A/F sensor. Air Fuel Ratio (A/F) Sensor Removal/Installation

Resistance Inspection (A/F sensor heater)

1. Disconnect the A/F sensor connector.

2. Measure the resistance between A/F sensor terminals 2 and 4.






- If it is not within the specification, replace the A/F sensor. Air Fuel Ratio (A/F) Sensor Removal/Installation

A/F sensor heater resistance
- 1-10 ohms

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