DTC P0133:00

A/F sensor circuit slow response

DETECTION CONDITION

The PCM monitors the A/F sensor terminal D current slow response and delayed response while the A/F fluctuation being provided when following monitoring conditions are met. If the average value of slow response and/or delayed response is more than specified value, the PCM determine that the A/F sensor has a deterioration.
MONITORING CONDITIONS
- Drive Mode 03 (EGR System, A/F sensor heater, HO2S heater, A/F sensor, HO2S and TWC Repair Verification Drive Mode)
- Following conditions are met:
  - A/F sensor heater monitor is completed.
  - Fuel system loop status is closed loop fuel control.
- ECT sensor and A/F sensor heater are normal
- Engine speed: 1, 200-3, 500 rpm
- Charging efficiency: 16-63 %
- Intake airflow amount: 5-40 g/s {0.7-5.2 lb/min}
- Engine coolant temperature: above 60°C {140°F}

Diagnostic support note

This is an intermittent monitor (A/F sensor, HO2S).
The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle.
FREEZE FRAME DATA (Mode 2)/Snapshot data is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

A/F sensor malfunction
- A/F sensor loose
- Exhaust system leakage
Purge solenoid valve malfunction
- Improper connection evaporative hose (purge solenoid valve side)
Fuel supply system malfunction or improper fuel line pressure
- Fuel leakage in fuel line from fuel distributor to fuel pump
- Fuel filter restricted
- Pressure regulator malfunction
- Fuel pump unit malfunction
Engine malfunction
- Insufficient engine compression
- Engine coolant leakage
A/F sensor malfunction
- Related wiring harness malfunction
- A/F sensor deterioration
PCM malfunction

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2) Perform the Freeze Frame PID Data Access Procedure. (See ON-BOARD DIAGNOSTIC TEST ). Is the DTC P0133:00 on FREEZE FRAME DATA (Mode 2)?	Yes	Go to the next step.
1		No	Go to the troubleshooting procedures for DTC on FREEZE FRAME DATA (Mode 2). (See DTC TABLE ).
2	VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED. Have the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor, HO2S related) been recorded?	Yes	Go to the next step.
2		No	Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
3	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Verify related Service Bulletins and/or on-line repair information availability. Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
3		No	Go to the next step.
4	VERIFY RELATED PENDING CODE AND STORED DTC Switch the ignition to off, then to ON (engine off). Perform the DTC Reading Procedure and Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST ). Is the DTC P0443:00 also present?	Yes	Go to the applicable DTC inspection. (See DTC P0443:00 ).
4		No	Go to the next step.
5	INSPECT INSTALLATION OF A/F SENSOR Inspect installation of A/F sensor. Is the A/F sensor installed securely?	Yes	Go to the next step.
5		No	Retighten the A/F sensor, then go to Step 14. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION ).
6	INSPECT FOR LEAKAGE FROM EXHAUST SYSTEM Reconnect the A/F sensor connector. Visually inspect if there is any exhaust gas leakage between exhaust manifold and A/F sensor. Is there any leakage?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
6		No	Go to the next step.
7	INSPECT PURGE SOLENOID VALVE AND EVAPORATIVE HOSE Inspect the purge solenoid valve and evaporative hose connection. (See PURGE SOLENOID VALVE INSPECTION ). (See INTAKE-AIR SYSTEM VACUUM HOSE ROUTING DIAGRAM ). Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14. (See PURGE SOLENOID VALVE REMOVAL/INSTALLATION ).
7		No	Go to the next step.
8	INSPECT FUEL LINE PRESSURE Switch the ignition to off. NOTE: If engine will not start, inspect fuel line pressure with ignition switches to ON. Inspect fuel line pressure with engine is running. (See FUEL LINE PRESSURE INSPECTION ). Is there any malfunction?	Yes	Go to the next step.
8		No	Go to Step 11.
9	INSPECT FOR FUEL LINE LEAKAGE Visually inspect for leakage from fuel line between fuel distributor to fuel pump. Is there any leakage?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
9		No	Go to the next step.
10	INSPECT FUEL FILTER Visually inspect for foreign materials or stain inside fuel filter. Is there any foreign materials or stain?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
10		No	Replace the fuel pump unit, then go to Step 14. (See FUEL PUMP UNIT REMOVAL/INSTALLATION ).
11	INSPECT ENGINE COMPRESSION Inspect the engine compression. (See COMPRESSION INSPECTION ). Is there any malfunction?	Yes	Repair or replace the malfunctioning parts according to the inspection results, then go to Step 14.
11		No	Go to the next step.
12	INSPECT SEALING OF ENGINE COOLANT PASSAGE Perform the "ENGINE COOLANT LEAKAGE INSPECTION". (See ENGINE COOLANT LEAKAGE INSPECTION ). Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
12		No	Go to the next step.
13	INSPECT A/F SENSOR Reconnect all disconnected connectors. Inspect the A/F sensor. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION ). Is there any malfunction?	Yes	Replace the A/F sensor, then go to the next step. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION ).
13		No	Inspect the related wiring harness. If there is any malfunction: Repair or replace the suspected wiring harness, then go to the next step. If there is no malfunction: Go to the next step.
14	VERIFY DTC TROUBLESHOOTING COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE ). Drive the vehicle under the monitoring conditions. Perform the Drive Mode 03 (EGR System, A/F sensor heater, HO2S heater, A/F sensor, HO2S and TWC Repair Verification Drive Mode). (See OBD-II DRIVE MODE ). Is the PENDING CODE for this DTC present?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION ). Go to the next step.
14		No	Go to the next step.
15	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
15		No	DTC troubleshooting completed.