Code result
P23FF
Bank 2 System B Air-Fuel Ratio Imbalance
Moderate severity
What it means
The secondary fuel system B on bank 2 (e.g. port-injection rail in a dual-injection engine, or LPG/CNG rail in a bi-fuel system) does not maintain calibrated mixture - lambda response on bank 2 is biased by an offset on the B system.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Secondary fuel system has drifted
highOne of the most commonly reported causes for this code — check this first.
Related help
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