Detailed guide for SPN 4364 FMI 18
Back to top ↑SCR efficiency faults trigger the countdown because emissions control is not meeting targets.\n\nRule out DEF quality, dosing, leaks, and sensor accuracy first.
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Share ↓SPN 4364 FMI 18Severity: CriticalPACCAR • PACCAR MX-13
SPN 4364 FMI 18: SCR conversion efficiency below normal (inducement risk)
Quick Answer
SCR conversion efficiency below normal (inducement risk)
Code
SPN 4364 FMI 18
Severity
Critical
Applies to
PACCAR • PACCAR MX-13
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Aftertreatment warning
- Inducement/derate risk
- Poor NOx conversion
Likely Causes
- DEF dosing issue
- NOx sensor drift/fault
- Exhaust leak or SCR catalyst aging
Common Fixes
- Verify DEF quality and dosing operation
- Check NOx sensor plausibility
- Inspect exhaust joints for leaks before blaming catalyst
Full technical sections↓
What does SPN 4364 FMI 18 mean?
Back to top ↑SCR conversion efficiency below normal (inducement risk)
Video walkthrough for SPN 4364 FMI 18
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SPN 4364 FMI 18, Def doser valve, failed regen
Channel: muhas1234 • View in BigRigFaults Media • YouTube source
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