P2197 - O2 Sensor Signal Biased/Stuck Lean - Bank 2, Sensor 1

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P2197 - O2 SENSOR SIGNAL BIASED/STUCK LEAN - BANK 2, SENSOR 1

Description: A universal heated oxygen sensor bank 2, sensor 1 (HO2S21) indicating lean 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 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 is leaking 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 .