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

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/shorted HO2S circuit
  • Open UO2SPC circuit
  • Corrosion or incorrect harness connections
  • Damaged HO2S
  • Damaged powertrain control module (PCM)

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

EGR System:
  • Leaking gasket
  • Stuck EGR valve
  • Leaking diaphragm or EGR vacuum regulator

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   - refer to PINPOINT TEST H . refer to PINPOINT TEST H .