P2457

P2457-EXHAUST GAS RECIRCULATION COOLING SYSTEM PERFORMANCE

For a complete wiring diagram Refer to Diagrams/Electrical.

Theory of Operation


This test will fail if the EGR Temperature is greater than a calibrated threshold for a calibrated period of time. This monitor protects the system from a failed EGR Cooler.

- When Monitored:
Engine running.

- Set Condition:
Exhaust gas recirculation temperature sensor is reading higher than a calibrated value for more than a calibratable period of time.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


Diagnostic Test


1. OTHER DTC'S
Ignition on, engine not running.
With the scan tool, read DTC's.
Are there any coolant temperature, fuel system or EGR valve DTC's?

Yes


- Repair other DTC's first
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 2



2. EGR COOLER
Remove the exhaust gas inlet and outlet to the EGR cooler.
Check the cooler for excessive blockages on the inlet and outlet orifices.
Is there exhaust gas fouling of the EGR cooler?

Yes


- Replace the EGR cooler.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 3



3. ENGINE OR FUEL MODIFICATIONS THAT EXCEED OEM SPECIFICATIONS
Inspect vehicle/engine for signs of Engine or Fuel modifications that exceed OEM specifications.
Are there signs the customer installed an modification kit that exceed OEM specifications?

Yes


- Return vehicle to customer. Explain that modifying the engine hardware/software may cause the engine to run outside of its normal operating limits.


No


- Repair complete.