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Home >> Ford >> 2000 >> Taurus LX, 3.0 2, AX4N >> Repair and Diagnosis >> External Pages >> Different car >> Section 378 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P2195: O2 Sensor Signal Biased/Stuck Lean - Bank 1, Sensor 1

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

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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
  • 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

Induction System:
  • Air leaks after the mass air flow (MAF) sensor
  • Vacuum leaks
  • PCV system
  • Improperly seated engine oil dipstick

EGR System:
  • Leaking gasket
  • Stuck EGR valve
  • Leaking diaphragm or EVR

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 . GO to Pinpoint Test H .