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Code 402. replaced egr valve and it still shows same code

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Replace the e g r valve position sensor and it`s hoses.

Posted on Aug 21, 2010

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Code p0402 comes up what do I do?

Code 402 means the EGR gas flow is excessive. On Ford products it could be the EGR valve or the sensor. Both components would need to be tested.

May 08, 2013 | 1996 Mercury Sable

2 Answers

Code p0402??

Code 402 means the computer has detected flow in the EGR valve when it should be closed.
The valve would need to be checked out.

May 06, 2013 | 2001 Isuzu Rodeo

2 Answers

Suburban error code reads 402

This means the EGR flow is excessive. The valve may be stuck open or another defect is triggering the EGR to open too much.

Nov 08, 2012 | 1999 Chevrolet Silverado 1500

1 Answer

402 code emision light on

Hi there:

DTC P0402 - Exhaust Gas Recirculation Flow (EGR) Excessive Detected

EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0402 code means that OBD detected an excessive amount of EGR.


You may notice drivability problems such as the engine may surge off idle. There may also be other symptoms.


A code P0402 most likely means one or more of the following has happened:

  • The DPFE (differential pressure) sensor is faulty and needs to be replaced
  • There is a blockage in the EGR (most likely carbon buildup)
  • The EGR valve is faulty
  • The EGR valve may not be opening due to a lack of vaccuum

Possible Solutions

With a P0402, it is common for people to replace the EGR valve, only to have the problem return. The most likely solution is to replace the DPFE sensor.

  • Check the voltage at the DPFE sensor both at idle and when the EGR is open
  • Replace the DPFE sensor

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa, have a nice day.

Aug 16, 2012 | Toyota Cars & Trucks

4 Answers

Grand carvan gives p402 code

This is not a cut and dry fault code. This means that more than one thing wrong can set the code in the computers memory. Here is the low down on the P0402 fault code. This is from the OBD2 fault code diagnostic book.

P0402 - Exhaust Gas Recirculation Flow Excessive Detected
Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Possible engine hesitation
Possible causes - EGR solenoid valve harness is open or shorted
- EGR solenoid valve circuit poor electrical connection
- EGR volume control valve stuck closed
- Dead (Weak) battery
- Faulty EGR temperature sensor and circuit
- Faulty EGR Valve
- EGR passage clogged
- Exhaust gas leaks

Jan 18, 2012 | Cars & Trucks

1 Answer

2006 ford f150 dtc codes 401, 402, 607

It is very possiable that you may be getting a false code that will reocure till egr problems are repaired. The ecu may be trying to compensate for egr problems causing it to send the 607 code

Oct 02, 2009 | 2006 Ford F-150

1 Answer

Fault code 402 have changed egr valve exh pressure sensor & egr solenoid nothing helps

po402--egr flow excessive, maybe carbon has built up in egr opening in engine!! or curcuit to egr valve is bad.

Aug 27, 2009 | 2002 Ford F150 Regular Cab

1 Answer

Every now and then the car wants to stall but it does not

You have verified the EGR valve will operate when vacuum is applied so the valve and chambers are good..correct? If thats the case, then
your issue here is the VSV (vaccum switching vavle), these intermittently get stuck. Follow the vaccum lines down behund the intake, you will find the vsv located on the back side of the block just above where the drive axle mounts to the block.
Replace this VSV and the modulator valve at the same time, they tend to fail togather.
Good luck, i hope this helps...please rate me a fixya

Jul 31, 2009 | Toyota Camry Cars & Trucks

1 Answer

I believe the corrected code should be 402.

DTC P0402 means that the OBD has detected a excessive amount of egr gases in the system. The EGR system has three major parts in it, The EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). P0402 was triggered by one of the following, The DPF is faulty and needs to be replaced. There is a blockage in theEGR valve from carbon build up and needs to be cleaned or replaced. The EGR valve is faulty Lack of vacuum to the EGR to opperate properly. Most will clean the EGR valve and if that does not fix the problem, check the connection to the DPF and or replace the DPF. Good luck and keep me posted. be glad to help.

Jun 05, 2009 | 1999 GMC Jimmy

1 Answer

Code 402 0n 2001 mazda tribute

A code P0402 most likely means one or more things has happened. The DPFE (differential pressure) sensor is faulty and needs to be replaced, there is a blockage in the EGR (most likely carbon buildup) or the EGR valve may not be opening due to a lack of vaccuum.

Jan 15, 2009 | 2004 Mazda Tribute

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