Detailed guide for SPN 4485 FMI 31
Back to top ↑Exhaust Gas Recirculation (EGR) systems clog with soot over time. When the valve hard-stops, power and emissions take a hit.
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Share ↓SPN 4485 FMI 31Severity: Critical
SPN 4485 FMI 31: EGR valve malfunction – mechanical fault exists
Quick Answer
EGR valve malfunction – mechanical fault exists
Code
SPN 4485 FMI 31
Severity
Critical
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- No power
- Rough idle
- Emissions fault
Likely Causes
- Stuck EGR valve
- Carbon blockage
- Actuator failure
Common Fixes
- Remove & clean EGR idle path
- Test actuator
- Replace part if binding
Full technical sections↓
What does SPN 4485 FMI 31 mean?
Back to top ↑EGR valve malfunction – mechanical fault exists
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