What is the P0402 fault number? What is the Exhaust Gas Recirculation fault code P0402? How do you fix the P0402 fault code What are the causes and symptoms of the P0402 error code?
What is the P0402 Fault code? What does it signify?
EGR controls the emission of nitrogen oxides by lowering the engine combustion temperature. Nitrous oxide gases form when the temperature inside the combustion chamber exceeds a certain point. These NOx gasses are controlled by the EGR system. EGR system malfunctions can occur just as with any component or system of the engine. P0402 is an OBD II fault code that refers to the EGR. If the Engine Control Module / ECM detects excessive flow in EGR, the code P0402 is issued.
Today, there are many different EGR systems. Each system uses an EGR valve, despite having different features. The PCM will command the EGR valve open when conditions permit exhaust gases to be recirculated back into the engine’s intake system. These inert gasses are introduced to the engine to lower combustion temperatures and reduce NOx emissions.
EGR is only needed in certain driving conditions. The PCM activates the engine fault lamp and stores the code P0402.
Similar EGR fault codes to P0400, P0401, and P0404, respectively, are P0405, P0405, and P0406, as well as P0406, P0407, and P0408, respectively.
What Are the Possible Causes of P0402 Fault Code
There are several possible triggers of the P0402 Code:
- – Defective differentialpressure sensor (DPFE) / available on certain vehicles
- – Defective EGR temperature sensor
- – Occlusion as a result of carbon build-up within the EGR channels
- – Defective EGR valve
- – Insufficient vacuum for the EGR valve to be opened
- – Loss of connections or damaged cables
- – EGR Control Circuit Problems
- PCM-related issues
What are the symptoms of P0402 Malfunction code?
Most malfunctions related to this code cause problems with driving. The symptoms you experience may vary depending on your vehicle. There are several symptoms that can be associated with P0402 code:
- – Illumination for the check engine light
- – Idle engine speed fluctuations
- – Engine stalling
- In extreme situations, the vehicle might not start.
How to Fix the P0402 Fault Code
- – Repairing, checking, and if necessary, replacing vacuum hoses, cables, and connectors
- – Replacing the EGR valve that is faulty
- – Replacing the exhaust catalyst
- – Replacing EGR’s temperature sensor
- – Clean the carbon from the EGR temperature sensor
- – Replacing EGR’s back pressure control valve
How serious is the P0402 fault code?
EGR with too much flow can make the engine hesitate, stall or not run smoothly at idle. This code may cause the engine not to start if the catalyst becomes blocked.
