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

DTC DESCRIPTION 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 rich 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
  • EVAP purge valve stuck open
  • Biased MAP sensor signal
  • Incorrect learned ethanol content
  • Contaminated MAF sensor (if equipped)
  • Positive crankcase ventilation (PCV) system
  • Contaminated oil
  • Oil overfill
  • Camshaft timing
  • Damaged universal HO2S21
  • Damaged PCM
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