Detailed guide for SPN 3216 FMI 2
Back to top ↑Intermittent circuits cause data noise that the ECM reads as suspect. Properly seating the sensor connector and cleaning it often solves this before sensor replacement.
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Share ↓SPN 3216 FMI 2Severity: Warning
SPN 3216 FMI 2: Intake NOx sensor circuit intermittent – data unstable
Quick Answer
Intake NOx sensor circuit intermittent – data unstable
Code
SPN 3216 FMI 2
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Aftertreatment warnings
- NOx readings bounce around
- Possible temporary derate
Likely Causes
- Connector issues
- Loose sensor pins
- Sensor data noise
Common Fixes
- Inspect and secure connector
- Test sensor signal under load
- Replace if erratic persists
Full technical sections↓
What does SPN 3216 FMI 2 mean?
Back to top ↑Intake NOx sensor circuit intermittent – data unstable
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