The engine is receiving too much fuel relative to air on bank 1. The computer has tried to reduce fuel delivery but cannot lean out the mixture enough. Excess fuel washes oil from cylinder walls and can damage the catalytic converter.
Find certified mechanics near you who can diagnose and repair P0172.
For informational purposes only. Diagnostic trouble codes are starting points for diagnosis, not definitive answers. Always consult a certified mechanic for proper diagnosis and repair. Estimated costs vary by vehicle, location, and shop rates.