How severe is this DTC?
A stored P2425 code is related to the exhaust gas recirculation system. It should not be classified as severe.
What are some symptoms of the code?
Symptoms of a P2425 fault code may include:
- No symptoms (except code storage)
- Increased cylinder temperature
- Reduced energy efficiency
- Exhaust temperature sensor codes
- Engine temperature sensor codes
What are some common causes of the code?
Causes of this code may include:
- Open or shorted EGR cooling valve control wires or connectors
- Low coolant level
- Faulty EGR temperature sensor(s)
- Clogged EGR cooler
- Engine overheating
- Faulty EGR cooling fan
What are the troubleshooting steps for P2425?
The engine cooling system must be filled to the appropriate level with the correct coolant before proceeding. If there are engine coolant leaks or if the engine is overheating, it must be repaired before diagnosing the stored P2425.
A diagnostic scanner, digital volt/ohmmeter, vehicle information source, and infrared thermometer (with laser pointer) are some of the tools I would use to diagnose a P2425.
I might start with a visual inspection of the wiring harnesses and connectors associated with the EGR temperature sensor and ECT sensor. Harnesses that are near hot exhaust pipes and manifolds should be carefully examined.
Connect the scanner to the vehicle’s diagnostic port and retrieve all stored codes and relevant freeze frame data. Before clearing codes and testing the vehicle, I like to note this information in case it turns out to be an intermittent code.
At this point, one of two things happens: either the PCM enters readiness mode (with no stored codes), or the P2425 is reset.
If the PCM further enters a ready state, the P2425 is intermittent and will be more difficult to diagnose. In many cases, the condition will need to worsen before an accurate diagnosis can be made.
If the P2425 is reset, use the scanner’s data stream to observe EGR temperature sensor data and ECT sensor data. Restricting the scanner’s data stream to include only relevant information will produce a faster data response. If the scanner indicates that EGR temperature and ECT are within acceptable parameters, suspect a faulty PCM or PCM programming error. This is your least likely scenario.
If the EGR temperature sensor data or ECT sensor data is erratic or does not meet desired parameters, test the sensor(s) in question by following the test procedures and specifications located in your vehicle information source. Sensors that do not match manufacturer specifications should be considered faulty.
Use the DVOM to test the EGR cooling valve control circuit if the sensors are functioning correctly. Remember to disconnect all associated controllers before testing. Repair or replace open or shorted circuits as needed.
If all EGR cooling valve control sensor circuits are intact, use the infrared thermometer to check the exhaust gas temperature at the EGR cooler (valve) inlet and at the EGR cooler outlet (with the engine running and at normal operating temperature). Compare your results with manufacturer specifications and replace faulty EGR cooling system components if necessary.
Installing high-performance EGR replacement parts and components may result in the storage of a P2425
