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Anonymous Posted on Sep 04, 2013

Egr valve p0401 prius 2010 - 2008 Toyota Prius

4 Related Answers

Anonymous

  • 16 Answers
  • Posted on Jan 19, 2009

SOURCE: How to replace EGR valve on 2000 camry V6?

If you have a P0401 code from a CEL, the first thing is to check the EGR vacuum modulator. It is a little well usually next to the EGR. Pop the cap off and dust the little sponge inside. Sometimes this gets stuffed up with carbon particles and causes recirculation problems. You should clean the tubes hooked to it while you are there. Reset the code and see if the light comes back.

Replacing the EGR is not a tidy job. It is an expensive part to replace and you will disconnect the three hoses and dismantle it from engine by two nuts. Save it for the later if the previous trick fails to work.

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Anonymous

  • 2004 Answers
  • Posted on May 27, 2009

SOURCE: p0401 code

P0401 indicates that EGR Flow Insufficient.

But if you have handled it and believe it is okay, I will give you tips on turning the warning off.

  • All trouble codes must be purged from the ECUs memory after repairing the faults. Otherwise, code(s) would remain in the ECUs memory indefinitely and would appear along with a new code in the event of a future problem.
  • Remove the EFI fuse (15A) for 30 seconds with the ignition switch OFF to clear any codes. It may take longer than 30 seconds, depending on ambient temperature (the lower the temperature, the longer the fuse must be left out).
  • Trouble codes can also be cleared by disconnecting the vehicle battery. However, other memory functions (clock, radio, etc.), will need to be reset.
  • After the codes are cleared, road test the vehicle (as applicable for the fault) and recheck if any codes reset. If so, it indicates that the trouble area has not been repaired correctly.
Or remove the battery terminal head for 10 minutes.

redds55

Ricky Peters

  • 2620 Answers
  • Posted on May 17, 2011

SOURCE: 2000 toyota camry code p0401 change egr valve

First did you reset the computer after replacing the EGR valve if you don't the computer doe'nt reconize the new sensor so it doe'nt reset the peremiters.Then check all passages and lines in the intake manifold there could be a clogg somewhere.Go to www.rockauto.com and you'll find EGR pressure sensor for under $30.00.

johnjohn2

Johnny Brown

  • 5763 Answers
  • Posted on Aug 17, 2011

SOURCE: I have a 2001 Toyota

Okay, the first test would be to start engine and put vacuum to egr valve so it opens the engine should drop in idle and may stall out, this test will tell you that the valve works and passages are clear but if the engine doesnt drop in idle then you may have a bad valve or block passage, if this is an electric egr then this is hard to test some of these without a scan tool, what you can check is the passage by removing the valve and then starting the engine and it will rev up and then use finger there will be two passages, one for exhaust that you will here and the other if you put finger over should be vacuum if you have both then i would look at valve. the valve contains the postion sensor as part of the valve,if it vacuum lets go back after the first test above you will now need to test the selinoid, this is computer controlled and allows vac to open the valve, these go bad often and is mostly a common problem, you will need to remove vac line that goes to valve, the other line should have vac with engine running.check it to make sure it does. if not check lines. next you will need a test light, remove the connector to solenoid and test for power and ground. you will have one of the two, the computer will send power or ground to open, you need to find out which is lacking, next is to start engine and apply power or ground whatever its lacking and vacuum should come out of the port to egr hose you removed, if no vac then the soleniod is the problem, make sure when checking connector you unplug it and test then plug in and applie what is no there. good day.

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1helpful
1answer

1996 Toyota Corolla. How do I fix code P0401?

Hi Joe

Like all solenoid valves, you can clean them with throttle body cleaner and then test the solenoid electronically with a 12 volt supply.

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P0401 : EGR Flow Insufficient on 1996 Toyota Corolla

OBD-Codes.com https://www.obd-codes.com > forums > viewtopic
Jan 20, 2007 - on EGR codes, we recommend replacing the EGR, vacuum modulator and VSV (if equipped) and cleaning out the carbon buildup to the intake from the ...
If that finds nothing wrong, remove the EGR valve and bypass tube and check them for cleanliness and blockages. If they are blocked, follow your maintenance manual's instructions for cleaning them out so you do not damage the valve, then replace them and reset the ECM.

Insufficient EGR Flow - P0401 Code - Toyota

0helpful
2answers

Fix 1999 Ford E150 van with code P0401

That's not what this code is about .P0401 - EGR Flow Insufficient Detected . Probably clogged egr passages .
P0401 - EGR Flow Insufficient Detected The EGR system is monitored during steady state driving conditions while the EGR is commanded on. The test fails when the signal from the DPF EGR sensor indicates that EGR flow is less than the desired minimum.
  • Vacuum supply
  • EGR valve stuck closed
  • EGR valve leaks vacuum
  • EGR flow path restricted
  • EGRVR circuit shorted to PWR
  • VREF open to D.P.F. EGR sensor
  • D.P.F. EGR sensor downstream hose off or plugged
  • EGRVR circuit open to PCM
  • VPWR open to EGRVR solenoid
  • D.P.F. EGR sensor hoses both off
  • D.P.F. EGR sensor hoses reversed
  • Damaged EGR orifice tube
  • Damaged EGRVR solenoid
  • Damaged PCM
Perform KOER self-test and look for DTC P1408 as an indication of a hard fault. If P1408 is not present, look for contamination, restrictions, leaks, and intermittents.
0helpful
1answer

Location of egr valve..2.4L....code p0401

Your vehicle doesn't have an EGR valve ! How did you come up with this code ? A code reader ? You need to have a factory scan tool if you want to see proper codes . Your vehicle has -
The camshaft position (CMP) actuator system is an electro-hydraulic operated device used for a variety of engine performance and operational enhancements. These enhancements include lower emission output through exhaust gas dilution of the intake charge in the combustion chamber, a broader engine torque range, and improved fuel economy. The CMP actuator system accomplishes this by changing the angle or timing of the camshaft relative to the crankshaft position. The CMP actuator simply allows earlier or later intake and exhaust valve opening during the four stroke engine cycle. The CMP actuator cannot vary the duration of valve opening, or the valve lift.
That P0401 is a generic code , you need factory tool for factory enhanced DTC'S !
0helpful
2answers

Egr fault code p0401

Hi there:

In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.

  • Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open
  • Clean out the EGR valve and/or tubing to remove deposits
  • Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)
  • Replace the DPFE sensor (with a good quality / OEM one)
  • Replace the EGR valve


Hope this helps.
4helpful
2answers

Check engine light code P0401 98 Ford expedition

OBD-II Trouble Code P0401 - Insufficient EGR Flow

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 EGR (DPFE). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR. You may notice drivability problems such as pinging (a.k.a. pre-ignition knock) when the engine is under load or the vehicle is at higher speeds. There may also be other symptoms.

A code P0401 most likely means one or more of the following has happened:
The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced
There is a blockage in the EGR (tube), most likely carbon buildup
The EGR valve is faulty
The EGR valve may not be opening due to a lack of vaccuum

Check it and keep us updated. Hope this helps (remember to rating this free answer).
6helpful
2answers

Fault code p0401

This error means Exhaust Gas Recirculation Flow Insufficient Detected.

You can deatils on the following site http://www.permoveo.ltd.uk/tabid/122/OBD-Error-Code/P0401/Diagnostics/Hyundai/Default.aspx

but for convenience I have reproduced that information here:
.
Generic OBD Error Code Details for P0401 Exhaust Gas Recirculation Flow Insufficient Detected What does this mean? OBD Code P0401refers to
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 EGR (DPFE). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR. SymptomsPossible sumptoms of OBD code P0401
You may notice drivability problems such as pinging (a.k.a. pre-ignition knock) when the engine is under load or the vehicle is at higher speeds. There may also be other symptoms. CausesPossible causes of OBD code P0401
A code P0401 most likely means one or more of the following has happened: •The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced•There is a blockage in the EGR (tube), most likely carbon buildup •The EGR valve is faulty •The EGR valve may not be opening due to a lack of vaccuum Possible SolutionsIn fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit. •Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open •Clean out the EGR valve and/or tubing to remove deposits•Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)•Replace the DPFE sensor (with a good quality / OEM one)•Replace the EGR valve Related CodesP0400 P0402 P0403
0helpful
1answer

1997 volvo 960, check engine light on with P0401. These motronic 4.4 do not have EGR, p0401 mean insufficient EGR flow. How do you fix this if there is no EGR?

A code P0401 most likely means one or more of the following has happened:
* The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (tube), most likely carbon buildup
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum

In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.
* Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open
* Clean out the EGR valve and/or tubing to remove deposits
* Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)
* Replace the DPFE sensor (with a good quality / OEM one)
* Replace the EGR valve

Check it and send us your advance.
1helpful
1answer

Check engine light stays on the code that keeps coming up is P0401 changed egr valve clened out carbon build up also smell gas when first start not driving and fuel millage not as good car runs good though...

Could be a EGR vacuum issue or temp sensor issue

Common Problems That Trigger the P0401 Code
  • Restriction in the EGR passages, usually caused by carbon buildup
  • Lack of a proper vacuum signal to the EGR Valve from EGR Vacuum Solenoid
  • EGR Vacuum Modulator is defective
  • EGR Temperature Sensor is defective
  • EGR Valve is defective
This is from:
http://repairpal.com/OBD-II-Code-P0401-Ford
3helpful
1answer

Ford Explorer : How to Troubleshoot the EGR P0401 Trouble Code

P0401 - Exhaust Gas Recirculation Flow Insufficient Detected

Possible Causes:
- Harness or connectors (EGR volume control valve circuit is open or shorted.)
- EGR volume control valve stuck closed
- EGR volume control solenoid valve
- Dead (Weak) battery
- EGR passage clogged
- Exhaust gas leaks
- Faulty EGR valve

Possible Solutions:
- Clean EGR Valve
- Replace EGR Valve
- Repair EGR harness or connector
- Replace EGR volume control solenoid valve
- Replace EGR volume control valve
11helpful
2answers

P0401 code

P0401


Insufficient EGR Flow
What does that mean?

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 EGR (DPFE). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR.
FB.init("dd7d9e9681341cde77587bc6a2029f6f"); OBD-Codes.com on Facebook Symptoms

You may notice drivability problems such as pinging (a.k.a. pre-ignition knock) when the engine is under load or the vehicle is at higher speeds. There may also be other symptoms.
Causes

A code P0401 most likely means one or more of the following has happened:

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

In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.

  • Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open
  • Clean out the EGR valve and/or tubing to remove deposits
  • Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)
  • Replace the DPFE sensor (with a good quality / OEM one)
  • Replace the EGR valve
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