Common Symptoms
- Check Engine Light illuminated
- Reduced engine power or performance
- Poor fuel economy
- Rough idle or hesitation
- Increased emissions or failed emissions test
- Engine overheating under load
Most Likely Root Causes
- Clogged or restricted EGR cooler
- Failed EGR cooler temperature sensor
- Low coolant level affecting EGR cooler
- EGR cooler bypass valve stuck or malfunctioning
- Damaged or leaking EGR cooler
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Component Location
The EGR cooler is typically mounted on the engine block or cylinder head, integrated into the EGR system between the exhaust manifold and intake.
Manufacturer Notes
Some diesel engines use complex EGR cooling systems with bypass valves that require proper coolant flow for accurate temperature monitoring.
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