Technical Description
Excessive Exhaust Gas Recirculation Flow (EGR) Detected
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to vehicles equipped with OBD-II. Although it is a generic code, the specific repair steps may vary depending on the make and model of the vehicle.
EGR stands for Exhaust Gas Recirculation. It is a component of the vehicle emissions system and is used to reduce combustion temperature and pressure in order to control Oxides of Nitrogen.
The EGR system generally consists of three parts: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These components work together to deliver the appropriate amount of recirculation based on factors such as engine temperature and load. The P0402 code indicates that the OBD system has detected an excessive amount of EGR.
Symptoms
You may experience drivability issues, such as the engine surging off idle. There may also be other symptoms present.
Causes
A code P0402 most likely indicates one or more of the following:
Possible Solutions
When encountering a P0402 code, it is common for individuals to replace the EGR valve, only to have the issue reoccur. The most likely solution is to replace the DPFE sensor.
Related EGR codes: P0400, P0401, P0403, P0404, P0405, P0406, P0407, P0408, P0409
