DTC: P1144

Search Bulletins/Recalls for P1144

Trouble diagnosis name: Heated oxygen sensor 1 rich shift monitoring (Bank 1)

Component Description

The heated oxygen sensor 1 is placed into the front tube. It detects the amount of oxygen in the exhaust gas compared to the outside air. The heated oxygen sensor 1 has a closed-end tube made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions. The heated oxygen sensor 1 signal is sent to the ECM. The ECM adjusts the injection pulse duration to achieve the ideal air-fuel ratio. The ideal air-fuel ratio occurs near the radical change from 1V to 0V.

DTC detecting condition:

• The maximum and minimum voltage from the sensor are not reached to the specified voltages.

Possible cause:

• Heated oxygen sensor 1
• Heated oxygen sensor 1 heater
• Fuel pressure
• Injectors
• Intake air leaks