OBD-II code · Powertrain (generic, extended)

P22FB NOx Sensor Performance - Sensing Element (Bank 1 Sensor 1)

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 with P22FB?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelyElement poisoned or end of life
  • Less likelySensor element aged beyond calibration window
  • Less likelySensor element contaminated by oil, soot or coolant

Symptoms

  • Check engine light or NOx warning on
  • AdBlue/DEF level or quality warning
  • Possible no-start countdown after ignore period
  • Failed emissions inspection (NOx)

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
1–3 h
Emissions test
Likely to fail
Parts involved
Nox Sensor

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.