Code result
P2201
NOx Sensor Range/Performance
High severity
What it means
The bank 1 NOx sensor reports values outside the plausibility window against modeled NOx and the downstream sensor. Often slow response from contamination by oil ash or coolant.
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
NOx sensor aged — slow response
highOne of the most commonly reported causes for this code — check this first.
Sensor element contaminated
mediumA plausible cause — test and verify before replacing parts.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Related help
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