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Home >> Ford >> 2012 >> Transit Connect Base, Van Cargo >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> DTC Diagnosis >> DTC P0133: O2 Circuit Slow Response (Bank 1, Sensor 1)
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DTC P0133: O2 Circuit Slow Response (Bank 1, Sensor 1)

P0133 - O2 CIRCUIT SLOW RESPONSE (BANK 1, SENSOR 1)

Description:  The PCM monitors oxygen sensor response time by commanding a calibrated fuel control routine. This routine sets the air fuel ratio to a calibrated limit to produce a predictable oxygen sensor signal amplitude. For vehicles with universal heated oxygen sensors (HO2S), this DTC sets when the oxygen sensor signal does not reach the predicted amplitude within a predetermined response time. For vehicles with HO2S, this DTC sets when the oxygen sensor amplitude is less than the predicted minimum amplitude limit.
Possible Causes: 
  • Contaminated HO2S
  • Exhaust leaks
  • Incorrect fueling
  • Mass airflow (MAF) sensor
  • Deteriorating HO2S
  • Inlet air leaks
Diagnostic Aids:  Access the HO2S test results from the scan tool to verify the DTC.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
E-Series 6.8L,
Escape 2.5L
Manual
Transmission,
Fiesta,
Fusion 3.5L,
Fusion 2.5L
Manual
Transmission,
MKZ,
Transit Connect
GO to PINPOINT TEST DW .
All others GO to PINPOINT TEST DZ .