Here are some more specific details about this code:
- Code Definition: EGR excessive flow detected
- Explanation: The EGR system routes a controlled amount of exhaust gas back into the air intake of the engine. This helps to reduce the formation of nitrogen oxides (NOx) emissions. If the EGR system detects that too much exhaust gas is flowing back into the intake, it will set the P0402 code.
Potential Causes of P0402:
- Faulty EGR valve
- Stuck open EGR valve
- Vacuum leak in the EGR system
- Faulty EGR position sensor
- Faulty PCM (powertrain control module)
It's important to note that while these are potential causes of the P0402 code, there could be other problems contributing to this issue. To accurately diagnose the root cause of the P0402 code in your Nissan Frontier pickup, it's best to consult with a qualified automotive technician or refer to the manufacturer's service manual for specific troubleshooting steps.
