What does code P21FC mean?

Q: What does code P21FC mean?

Fuel Control System B Too Lean at Higher Load (Bank 1). P21FC means the engine computer has detected a lean condition in the fuel control system for bank 1 while the engine is under higher load, such as during acceleration or climbing a hill. The computer commands extra fuel to maintain the correct air-fuel ratio, but the oxygen sensor reports that the mixture remains too lean, so the computer sets this code.

DTC codes / P21xx · Fuel and air metering / P21FC

P21FCFuel Control System B Too Lean at Higher Load (Bank 1)

P21FC means the engine computer has detected a lean condition in the fuel control system for bank 1 while the engine is under higher load, such as during acceleration or climbing a hill. The computer commands extra fuel to maintain the correct air-fuel ratio, but the oxygen sensor reports that the mixture remains too lean, so the computer sets this code.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.