Detailed guide for SPN 4752 FMI 18
Back to top ↑When the EGR cooler is not cooling, soot production increases.\n\nIf coolant starts disappearing, take it seriously.
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Share ↓SPN 4752 FMI 18Severity: Warning
SPN 4752 FMI 18: EGR cooler efficiency below normal (soot/regens increase)
Quick Answer
EGR cooler efficiency below normal (soot/regens increase)
Code
SPN 4752 FMI 18
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- More soot and frequent regens
- Possible power loss
- EGR-related faults may stack
Likely Causes
- EGR cooler restricted
- Cooler leaking internally
- Cooling flow issues
Common Fixes
- Inspect for coolant loss or contamination signs
- Check EGR temps if available
- Service/replace cooler if efficiency is truly low
Full technical sections↓
What does SPN 4752 FMI 18 mean?
Back to top ↑EGR cooler efficiency below normal (soot/regens increase)
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