2014 Ford Focus Titanium, 4D Hatchback, Automatic DCT Trans, Gas/EthanolFACTORY OEM SERVICE PROCEDURE

P2198 - O2 Sensor Signal Biased/Stuck Rich - Bank 2, Sensor 1

P2198 - O2 SENSOR SIGNAL BIASED/STUCK RICH - BANK 2, SENSOR 1

Description:  A universal heated oxygen sensor bank 2, sensor 1 (HO2S21) indicating rich at the end of a test is trying to correct for an over lean condition. This DTC sets when the fuel control system no longer detects switching for a calibrated amount of time.
Possible Causes: 
  • Water in the harness connector
  • UO2SPC21 circuit open
  • Corrosion
  • Incorrect connections
  • Excessive fuel pressure
  • Leaking or contaminated fuel injectors
  • Leaking fuel pressure regulator
  • Low fuel pressure or running out of fuel
  • EVAP purge valve stuck open
  • Air leaks after the mass airflow (MAF) sensor (if equipped)
  • Vacuum leaks
  • Positive crankcase ventilation (PCV) system
  • Incorrectly seated engine oil dipstick
  • Leaking gasket
  • Stuck EGR valve
  • Leaking diaphragm or EGR vacuum regulator
  • Oil overfill
  • Camshaft Timing
  • Cylinder compression
  • Exhaust leaks before or near the universal HO2S21
  • Damaged universal HO2S21
  • Damaged PCM
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST H: FUEL CONTROL .
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