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 DTC P0133 [L8, LF, L3]

DTC P0133 [L8, LF, L3]

id0102a1804800

DTC P0133

A/F sensor circuit problem

DETECTION CONDITION

• A/F sensor malfunction is detected by measuring of the average frequency of A/F sensor signal, time required to pass from rich to lean, time required to pass from lean to rich.
• The average frequency of A/F sensor signal is more than the threshold value.
MONITORING CONDITIONS
- 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 and normal.
- Engine speed: 1410-3500 rpm
- Charging efficiency: 15-59 % (MTX), 20-59 % (ATX)
- Engine coolant temperature above 70 °C {158 °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.
• DIAGNOSTIC MONITORING TEST RESULTS is available.
• PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• A/F sensor deterioration
• A/F sensor malfunction
• A/F sensor looseness
• Fuel pump malfunction
• Clogged or restricted fuel filter (built-in fuel pump unit)
• Fuel leakage in fuel line between fuel distribution pipe and fuel pump
• Exhaust system leakage
• Purge solenoid valve malfunction
• Improper connection purge solenoid hose
• Insufficient compression
• Engine malfunction (Engine coolant leakage)

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
VERIFY RELATED PENDING AND STORED DTC
• Turn the ignition switch off, then to the ON position (Engine off).
• Verify the pending or stored DTCs using the WDS or equivalent.
• Is the DTC P0443 also present?
Yes
Go to DTC P0443 troubleshooting procedures, then go to Step 13.
No
Go to the next step.
4
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is the DTC P0133 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to troubleshooting procedures for DTC on FREEZE FRAME DATA.
5
VERIFY CURRENT INPUT SIGNAL STATUS
• Warm up the engine.
• Access O2S11 PID using the WDS or equivalent.
• Inspect PID under following accelerator pedal conditions in PARK (ATX) or NEUTRAL (MTX).
• Is PID normal?

- - 1.0 -1.0 A when idle

- More than 0.25 mA just after release of accelerator pedal (lean condition).

Yes
Go to Step 8.
No
Go to the next step.
6
INSPECT INSTALLATION OF A/F SENSOR
• Inspect if the A/F sensor is loosely installed.
• Is the A/F sensor installed securely?
Yes
Go to the next step.
No
Retighten the A/F sensor, then go to Step 13.
7
INSPECT GAS LEAKAGE FROM EXHAUST SYSTEM
• Visually inspect if there is any gas leakage is found between the exhaust manifold and A/F sensor.
• Is there gas leakage?
Yes
Repair or replace the malfunctioning exhaust part, then go to Step 13.
No
Replace the sensor, then go to Step 13.
8
INSPECT LONG TERM FUEL TRIM
• Access the LONGFT1 PID.
• Compare it with FREEZE FRAME DATA recorded at Step 1.
• Is it below FFD value?
Yes
The engine is driven under rich condition. Go to the next step.
No
The engine is driven under lean condition. Go to Step 10.
9
INSPECT FUEL LINE PRESSURE (EXCESSIVE FUEL LINE PRESSURE)
• Turn the ignition switch off.
• Inspect the fuel line pressure while the engine running.
• Is the fuel line pressure normal?
Yes
Go to Step 12.
No
Inspect the fuel pump maximum pressure, and fuel return pipe for clogging.
• If there is any problem, repair or replace the parts.
• If all items above are normal, replace the fuel pump unit.
Then go to Step 13.
10
INSPECT FUEL LINE PRESSURE (LOW FUEL LINE PRESSURE)
• Turn the ignition switch off.
• Inspect the fuel line pressure while the engine running.
• Is the fuel line pressure normal?
Yes
Go to Step 12.
No
Go to the next step.
11
INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DELIVERY PIPE
• Visually inspect the fuel line for any leakage.
• Is there fuel leakage?
Yes
Replace the fuel line, then go to Step 13.
No
Inspect the fuel filters for the following:
• Foreign material or stain inside the fuel filter (low-pressure side)
Perform the following actions according to the result.
• If foreign material or stain is found inside the fuel filter (low-pressure side), clean the fuel tank and fuel filter.
• If normal, replace the fuel pump unit.
Then go to Step 13.
12
INSPECT SEALING OF ENGINE COOLANT PASSAGE
• Perform the "ENGINE COOLANT LEAKAGE INSPECTION".
• Is there any malfunction?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
Then go to the next step.
13
VERIFY TROUBLESHOOTING OF DTC P0133 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Turn the ignition switch to the ON position. (Engine off)
• Clear the DTC from the memory using the WDS or equivalent.
• Perform the A/F sensor heater, HO2S heater, A/F sensor, HO2S, and TWC Repair Verification Drive Mode. (See OBD DRIVE MODE [L8, LF, L3].)
• Is the PENDING CODE for this DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
14
VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
• Are any DTC present?
Yes
Go to the applicable DTC troubleshooting.
No
Troubleshooting completed.