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Test AZ: Exhaust Gas Recirculation (EGR) Cooler System Performance

PINPOINT TEST AZ: EXHAUST GAS RECIRCULATION (EGR) COOLER SYSTEM PERFORMANCE


Flow Chart:






This pinpoint test is intended to diagnose the following:
- engine overheating condition
- restricted EGR cooler
- charge air cooler (CAC) system

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AZ1 : PRELIMINARY DIAGNOSIS

- Carry out a visual inspection.
- Retrieve and record all DTCs.
- Record the freeze frame data
- Are any DTCs other than DTC P2457 retrieved?






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AZ2 : CHECK FOR ENGINE OVERHEATING CONDITION

- Check for engine overheating condition or loss of coolant condition.
- Is the engine overheating or losing coolant?






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AZ3 : CHECK THE CAC SYSTEM FOR DAMAGE

- Check the CAC system for:
- air restrictions
- debris
- damaged clamps
- damaged cooler fins
- damaged hose
- leaks

- Is the CAC system operating correctly?






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AZ4 : RECREATE EGR COOLER PERFORMANCE CONDITIONS

- Clear the PCM DTCs.
- Road test the vehicle to recreate the EGR cooler performance condition DTC P2457 using the freeze frame data.
- Retrieve and record the PCM continuous DTCs
- Is DTC P2457 retrieved?






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AZ5 : CHECK THE EGR COOLER FOR RESTRICTIONS

- Remove the EGR cooler.
- Check the EGR cooler exhaust port, coolant port and coolant hose for restrictions.
- Is the EGR cooler exhaust port restricted?