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DTC P0133-00: Linear air-fuel ratio sensor slow response
 
 
 
 
TECHNICAL DESCRIPTION
  • The ECM effects air-fuel ratio feedback control in accordance with the signals from the linear air-fuel ratio sensor.
  • If the linear air-fuel ratio sensor has deteriorated, corrections will be made by the heated oxygen sensor (rear).
 
 
DESCRIPTIONS OF MONITOR METHODS
If the response speed of the linear air-fuel ratio sensor to the change in the air-fuel ratio is too slow, the DTC is set as the linear air-fuel ratio sensor deterioration.
 
 
MONITOR EXECUTION
Continuous.
 
 
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
  • Linear air-fuel ratio sensor heater monitor
  • Misfire monitor
  • Fuel system monitor
Sensor (The sensor below is determined to be normal)
  • Mass airflow sensor
  • Engine coolant temperature sensor
  • Intake air temperature sensor
  • Barometric pressure sensor
  • Throttle position sensor
  • Fuel tank pressure sensor
 
 
DTC SET CONDITIONS
Logic Flow Chart
Check Conditions
  • Engine speed is between 1,281 and 3,500 r/min.
  • Volumetric efficiency is between 35 and 85 percent.
  • Mass airflow sensor output is 1.2 g/sec (0.042 oz./sec) or more.
  • Engine coolant temperature is more than 60°C (140°F).
  • Under the closed loop air-fuel control.
  • Vehicle speed is lower than 1.5 km/h (1 mph).
  • Short-term fuel trim is between –25 and +25 percent.
  • More than 8 seconds have elapsed after the above mentioned conditions have been met.
  • During the drive cycle, the ECM performs monitoring with the accumulated total time of 10 seconds, 5 times.
Judgment Criteria
  • During accumulated 10 seconds, the average frequency is less than 8 times.
  • During accumulated 10 seconds, the frequency is less than 17 times.
 
 
FAIL-SAFE AND BACKUP FUNCTION
None.
 
 
OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function, OBD-II Drive Cycle – Pattern 5 OBD- II DRIVE CYCLE.
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
  • Linear air-fuel ratio sensor failed.
  • Connector damage.
 
 
DIAGNOSIS
Required Special Tools:
  • MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
  • MB992745: V.C.I.-Lite main harness A
  • MB992747: V.C.I.-Lite USB cable short
  • MB992748: V.C.I.-Lite USB cable long
1.STEP 1. Test the OBD-II drive cycle after replace the linear air-fuel ratio sensor.
After erasing the DTC, carry out test drive with the drive cycle pattern, and recheck the DTC.
(1) Use scan tool (M.U.T.-III SE) to erase the DTC.
(2) Carry out test drive with the drive cycle pattern (Refer to Diagnostic Function, OBD-II Drive Cycle – Pattern 5 OBD- II DRIVE CYCLE).
(3) Use scan tool (M.U.T.-III SE) to recheck the DTC.
Q: Is DTC P0133-00 set?
Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION).
Intermittent malfunction (Refer to GENERAL INFORMATION, General Information – How to Use Troubleshooting/Inspection Service Points – How to Cope with Intermittent Malfunctions HOW TO COPE WITH INTERMITTENT MALFUNCTIONS).