P0172

DTC P0171 / P0172: System Too Lean / Too Rich (Sensor-1, Bank-1)

Wiring Diagram

Wiring Diagram:

A/F Sensor Description

Refer to A/F Sensor Description.

DTC Detecting Condition and Trouble Area

DTC Detecting Condition And Trouble Area:

DTC Confirmation Procedure

WARNING:
^ When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
^ Road test should be carried out by 2 persons, a driver and a tester, on a level road.

NOTE: Check to make sure that the following conditions are satisfied when using this "DTC Confirmation Procedure".

EVAP leak check model:
^ Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
^ The following DTCs are not detected: DTCs related to MAF sensor and A/F sensor

Non-EVAP-leak-check model:
^ Intake air temperature at engine start: -10 °C (14 °F) to 80 °C (176 °F)
^ Intake air temperature: -10 °C (14 °F) to 70 °C (158 °F)
^ Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
^ The following DTCs are not detected: DTCs related to MAF sensor, ECT sensor, IAT sensor, barometric pressure sensor and A/F sensor

1. With ignition switch turned OFF, connect scan tool.
2. Turn ON ignition switch and print Freeze Frame Data or write them down using scan tool.
3. Clear DTC using scan tool.
4. Start engine and warm up to normal operating temperature.
5. Operate vehicle with condition as noted freeze frame data for 5 min.
6. Stop vehicle and check DTC and pending DTC.

DTC Troubleshooting

Step 1-7:

Step 8-9: