P0402 OBD Error Code: Problem & Solutions

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The fault code P0402 can be described as Exhaust Gas Recirculation Flow Excessive Detected. The EGR stands for Exhaust Gas Recirculation. Its main function is to reduce combustion temperature as well as pressure to control Oxides of Nitrogen and it is a part of the vehicle emissions system.

The EGR system is comprised of three parts: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). All of these three parts work together to deliver the right amount of recirculation based on engine temperature, load, etc. The trouble code P0402 would mean that an excessive amount of EGR has been detected by the OBD.

What causes this problem with the Exhaust Gas Recirculation Flow Excessive Detected?

• Defects in the EGR volume control valve
• There can be open or shorted EGR solenoid valve harness
• EGR volume control valve stuck might be open
• Flaws in the EGR temperature sensor and circuit
• Bad electrical connection in the EGR solenoid valve circuit

1. Crankshaft Position Sensor - A faulty Crankshaft Position Sensor can be troublesome. You can always rely on us as we have best auto parts for our customers.
2. Oil Pressure Sender - If everything is alright with Catalytic Converter, then there is surely some defect in Oil Pressure Sender. Get it replaced before the situation gets worse.
3. Catalytic Converter - P0402 code can display due to some flaws in the Catalytic Converter. So, it is very important to replace the Catalytic Converter with us at equitable prices.
4. Engine Coolant Temperature Sensor - Do you remember when was the last time you got your car Engine Coolant Temperature Sensor inspected up? A defective Engine Coolant Temperature Sensor can cause a lot of issues like displaying P0402 code.
5. EGR Valve Gasket - Are there some faults in your EGR Valve Gasket? Don’t waste time and get them replaced or else P0402 code can turn up.
6. MAP Sensor - Everything is fine with EGR Valve Gasket and still P0402 code triggering? Then you must get your MAP Sensor checked.
7. Mass Air Flow Sensor - There can be some issues with the Mass Air Flow Sensor due to which you may see P0402 code appearing over and over again. Visit us to buy best quality Mass Air Flow Sensor online.

There could be countless symptoms which that would accompany with this fault code. Willing to know some common symptoms of OBD Trouble Code P0402? Your wish is our demand. Have a look at them below:

Common Symptoms

• The engine might start running roughly
• Appearance of the check engine light
• There can be exhaust leaks in the engine EGR system

Looking out for some ways with the help of which you can correct this fault code? Then you have arrived at the correct place. We are here to help you out, so you must check out the steps mentioned below as follows:

• If there is a broken catalyst in the exhaust, then it should be replaced
• It is very important to replace the stuck open EGR valve
• You can always replace an EGR temperature sensor or cleaning the carbon off of it to repair it if it registers too much of a temperature change
• The EGR backpressure control valve should be replaced as per the requirement

Don’t get tensed if you are still facing any of these issues as we care for our customers and that’s why we offer a good range of Egr valve, Throttle Position Sensor, Mass Air Flow Sensor Cleaner, Egr Temperature Sensor and a lot more. We are sure that now all your issues would be resolved.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P0402 code to be stored:

• The codes should be scanned and document the freeze frame data in order to verify the issue
• Then you must clear the engine and ETC codes and road test the vehicle to verify that the code comes back
• Visually inspect the vacuum hoses, wiring, connections to the EGR valve, and control solenoid, along with the EGR temperature sensor and back pressure transducer
• Disconnect and check to see if the EGR valve vacuum can be controlled to the valve when the control solenoid opens on light-to-medium acceleration and not just when it is open fully
• The exhaust catalyst for damage should be checked or excessive back pressure on the EGR system
• Remove the EGR valve and temperature sensor to check for carbon holding the EGR valve open or the EGR bleed port not being blocked with carbon not allowing the valve to bleed off vacuum

Common Mistakes When Diagnosing The P0402 Code

• It is very important to check the EGR pressure transducer to see if it can control the EGR valve opening rather than replacing the EGR valve directly
• Another mistake can be not checking to see if the EGR valve is being held open mechanically by a piece of carbon before replacing it