LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2008 >> 5 Touring, 2.3 L >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3) >> DTC P0133 [L3] >> Notes
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0133 [L3]: Notes

DTC P0133 [L3] DETECTION CONDITIONS AND POSSIBLE CAUSES

DTC P0133 Front HO2S circuit slow response
DETECTION CONDITION 
  • The PCM monitors the peak differential value of oxygen sensor signal after A/F fluctuation being provided when the following conditions are met. If the peak differential value is lower than the threshold value. The PCM determines that the front HO2S circuit is slow.

    MONITORING CONDITIONS 

    • HO2S heater, HO2S, and TWC Repair Verification Drive Mode
    • Following conditions are met:
      • Front HO2S heater monitor is completed.
      • Fuel system loop status is closed loop fuel control.
    • Engine speed: 1,500-3,500 rpm (MTX), 1,350-3,500 rpm (ATX) 
    • Absolute load: 20-60 % (MTX), 21-60 % (ATX)  (at engine speed: 2,500 rpm) 
    • Intake air volume: 5-40 g/s {0.7-5.2 lb/min} 
    • Engine coolant temperature above 70 °C {158 °F} 

Diagnostic support note 
  • This is an intermittent monitor. (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 the first drive cycle.
  • FREEZE FRAME DATA is available.
  • DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Front HO2S deterioration
  • Front HO2S malfunction
  • Front HO2S 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)