OBD-II code · Powertrain (generic, extended)
P2201 NOx Sensor Range/Performance (Bank 1)
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 with P2201?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyNOx sensor aged — slow response
- PossibleSensor element contaminated
- Less likelySensor element aged beyond calibration window
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
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2.5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Nox Sensor
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.