Code result
P22FB
NOx Sensor Performance - Sensing Element
High severity
What it means
The wide-band sensing element of the NOx sensor on bank 1 sensor 1 reports an internal performance fault — typically poisoning, condensate damage, or end of service life.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Element poisoned or end of life
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor element contaminated by oil, soot or coolant
lowLess common, but worth ruling out after the more likely causes.
Related help
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