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

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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
Diagnostic Aids:
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to Pinpoint Test H .