DTC P0133: - O2 Circuit Slow Response (Bank 1, Sensor 1)

2009 Ford Fusion SEL, 3.0 1, FWDSECTION DTC P0133: - O2 Circuit Slow Response (Bank 1, Sensor 1)
DTC P0133: - O2 CIRCUIT SLOW RESPONSE (BANK 1, SENSOR 1)

Description:  For the Flex, MKS, Sable PZEV, Taurus PZEV, Taurus X PZEV, the powertrain control module (PCM) commands an air/fuel ratio that changes in the shape of a square wave. The PCM calculates the length of the resulting signal from the HO2S. The test fails when the length of the signal is less than a calibrated limit.
For all others, the PCM checks the HO2S signal frequency and amplitude. The test fails when the frequency and amplitude less than a calibrated limit.
Possible Causes: 
  • Contaminated HO2S
  • Exhaust leaks
  • Short/open wiring
  • Incorrect fueling
  • MAF sensor
  • Deteriorating HO2S
  • Inlet air leaks
Diagnostic Aids:  Access the HO2S test results from the generic OBD menu to verify the DTC.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
E-Series
4.6L,
E-Series
5.4L,
Expedition,
F-150,
Flex,
MKS,
Navigator,
Sable PZEV,
Taurus PZEV,
Taurus X
PZEV
- - GO to Pinpoint Test DZ .
All others - - GO to Pinpoint Test DW .
RENDER: 1.0x

NO RELATED

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