NOx Sensor Circuit Intermittent Bank 2
What it means
P2217 means the PCM saw an intermittent or erratic signal from the bank 2 NOx sensor circuit — the reading briefly cut out or jumped. The NOx sensor lets the emissions system measure nitrogen-oxide output, so a dropping signal usually points to a flexing or corroded wire or connector rather than a dead sensor. There's often no immediate driving symptom, though many diesels will eventually derate power if NOx monitoring stays unreliable.
Can I keep driving? Drivable at first, but many diesels eventually derate power when NOx monitoring is unreliable — repair before that happens.
Common symptoms
What you'll notice
- Check-engine light on (may come and go)
- Often no immediate driving symptom
- Possible increased NOx emissions / emissions-test failure
- On some diesels, an eventual reduced-power (derate) warning
Common causes
Most likely first
- Intermittent open/short in the bank 2 NOx sensor wiring (chafed or flexing harness)Likely
- Poor or corroded connection at the sensor or module connectorCommon
- Faulty NOx sensor on bank 2Common
- Faulty PCM/emissions control module (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data, then wiggle-test the NOx sensor connector and harness to reproduce the dropout.
- Inspect the connector for corrosion, spread pins, or looseness.
- Check the signal and power/ground circuits for intermittent opens while flexing the harness.
- Repair any chafed or intermittent wiring on the bank 2 NOx circuit.
- If the wiring checks good, replace the bank 2 NOx sensor and re-test.
FAQ
Quick answers
Is it safe to drive with P2217?+
Can I just clear P2217?+
Related codes
Often seen with P2217
Read & clear P2217 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.