DTC P2195: O2 Sensor Signal Biased/Stuck Lean - Bank 1, Sensor 1

2005 Ford Taurus SEL, 4D SedanSECTION DTC P2195: O2 Sensor Signal Biased/Stuck Lean - Bank 1, Sensor 1
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
P2195 - O2 SENSOR SIGNAL BIASED/STUCK LEAN - BANK 1, SENSOR 1

Description:  A heated oxygen sensor (HO2S) indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time.
Possible Causes:  Electrical:
  • Short to VPWR in the harness or HO2S
  • Water in the harness connector
  • Open UO2SPC circuit
  • Corrosion or incorrect harness connections
  • Damaged universal HO2S

Fuel System:
  • Excessive fuel pressure
  • Leaking/contaminated fuel injectors
  • Leaking fuel pressure regulator
  • Low fuel pressure or running out of fuel
  • Vapor recovery system

Intake Air System:
  • Air leaks after the mass air flow (MAF) sensor
  • Vacuum leaks
  • Positive crankcase ventilation (PCV) system is leaking or the valve is stuck open
  • Incorrectly seated engine oil dipstick

Exhaust Gas Recirculation (EGR) System:
  • Leaking gasket
  • Stuck EGR valve

Base Engine:
  • Oil overfill
  • Camshaft timing
  • Cylinder compression
  • Exhaust leaks before or near the HO2S(s)
Diagnostic Aids:   
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST H .
RENDER: 1.0x

NO RELATED

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