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Anyone got check engine light P0401 EGR shows up in every few weeks...

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by us_matrix, Apr 24, 2014.

  1. us_matrix

    us_matrix Member

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    My 2010 Prius with 72k miles on it. I bought a OBDII scanner and read P0401 Exhaust Gas Recirculation Flow Insufficient Detected. The check engine light comes on for few days, then go away for few weeks and then come back again. It's been doing the exact same thing (Come on for few days and then go away) in last few months. But I do not feel any different in terms of driving.
    Have anyone experienced this issue and how to fix it? I am thinking to stop by dealer to check but since it is out of warranty not sure how much it costs to fix it?

    Thanks.
     
    #1 us_matrix, Apr 24, 2014
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  2. bisco

    bisco cookie crumbler

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    perhaps you need a new egr valve. should be a 5 year warranty on emissions.
     
    #2 bisco, Apr 24, 2014
  3. us_matrix

    us_matrix Member

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    I thought the warranty only up to 2 years including EGR.... Anyone got that covered under 5 year warranty? I checked the gas cap but it is tighten. Anyone other thought ?

    Thanks.
     
    #3 us_matrix, Apr 24, 2014
  4. bisco

    bisco cookie crumbler

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    should be in your warranty book or a quick call to the dealer.
     
    #4 bisco, Apr 24, 2014
  5. jjPrius

    jjPrius Junior Member

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    Would it not be covered under the 15 year / 150K CARB-related warranty?
     
    #5 jjPrius, Apr 24, 2014
  6. Mike500

    Mike500 Senior Member

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    A loose hose, valve cover or any other vacuum leak will cause an EGR error.
     
    #6 Mike500, Apr 24, 2014
  7. us_matrix

    us_matrix Member

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    Not sure above symptoms lead to my issue. Because the check engine light comes on for few days ( May be it detect low pressure or whatever other problems) and then go away. Few weeks later comes back again in last 6 months......
     
    #7 us_matrix, Apr 24, 2014
  8. jjPrius

    jjPrius Junior Member

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    There is a TSB released on this issue; the EGR valve is covered for 15 years / 150K miles for the Prius liftback in California. Good luck!

    Jeff
     

    Attached Files:

    #8 jjPrius, Apr 24, 2014
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  9. us_matrix

    us_matrix Member

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    Good news! Took it to the dealer and the P0401 EGR check engine light issue is under emission warranty. Dealer replace EGR under warranty ^,^.
    If you have this come up. Take it to dealer to replace under warranty!

    Cheers!
     
    #9 us_matrix, May 29, 2014
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  10. cproaudio

    cproaudio Speedlock Overrider

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    #10 cproaudio, Jul 12, 2016
  11. Robin hood

    Robin hood New Member

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    There was a bull item that came out and if your egr part is 25620-37110 then it should be replaced with part number
    25620-37120. I found one for like 60 bucks on eBay. Hopefully it fixes the p0401 fault I got since I got the Prius.
     
    #11 Robin hood, Dec 27, 2016
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  12. bisco

    bisco cookie crumbler

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    welcome, and thank you!(y)
     
    #12 bisco, Dec 27, 2016
  13. Raytheeagle

    Raytheeagle Senior Member

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    How many miles on your Prius? Are you the original owner?

    I got a used egr for $35 last year around this time from a local salvage yard. Also bought the egr cooler for $65 and have a spare set that will go on at a later time:).

    Never got the P0401 code but did it for other reasons. The valve you have on there now is probably carbon deposited up and will work again once it is actuated a time or two.
     
    #13 Raytheeagle, Dec 27, 2016
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  14. rtvanhook

    rtvanhook New Member

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    "rough idle and/or rattle noise from the transaxle at cold start due to a sticking Exhaust Gas Recirculation (EGR) Valve" is supposedly covered under a Warranty Enhancement Program, but not really--because the dealer can't recreate it (tends to happen on cold mornings after it's been parked for a while). I showed them this video of mine doing it:



    Not good enough for the dealer--or the Toyota Customer Assistance Center. To recreate the condition, it has to be cold and the vehicle has to be parked for a while. So to make sure your dealer can see it misbehave, you must a) identify a cold night at least a week in advance, and b) then leave your car at the dealership for that week. Ugh.
     
    #14 rtvanhook, Jan 11, 2018
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  15. Infini

    Infini Member

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    Ok I got this code as well and have GOOD NEWS. I have also been burning oil like crazy. So far this was my results with the dealer today.

    It was the EGR Valve. They warrantied it. Replaced the valve kit, gasket and cooler.

    My 2010 Prius IV has just under 80k miles.

    With the burning oil they can’t do anything till an extended warranty is issued from Toyota and he hinted they will since it’s happened with the Scion xB and other models of similar engine size. But I have to check my oil levels every month now lol.

    They also found hybrid battery blower needed new filter. That cost me a bit in labor. Anyways don’t Wanna go off topic. Just it’s good they warrantied the egr.
     
    #15 Infini, Jun 7, 2018
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  16. audiodave

    audiodave Active Member

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    EGR have anything to do with the oil burning?

    Posted via the PriusChat mobile app.
     
    #16 audiodave, Jun 8, 2018
  17. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Almost certainly just needed cleaning, and then it would be good as new. But dealerships mostly just throw parts at problems. You can do this yourself, for pretty much zero outlay.

    The 4th gens have the EGR inlet downstream of the catalytic converter; with 3rd gen it's upstream. Seems a tacit admission, that the 3rd gen design is clog prone.

    Here's a good thread on cleaning the EGR circuit:

    EGR & Intake Manifold Clean Results | PriusChat

    And related, on Oil Catch Can:

    Oil Catch Can, Eliminate that knock! | PriusChat

    For intake manifold clean up, watch @NutzAboutBolts video:

    Nutz About Bolts Prius Maintenance Videos | PriusChat

    Also check out his EGR cleaning video while you're there. It ties into some of his other videos, for parts removal: the spark plug change video in particular is must watch.

    He's also got a video for hybrid battery fan cleaning, another must watch. I'd only comment that you can do this without rear seat removal, just push apart the opening between seat and back, reach in with 12 mm socket on an extension to remove one bolt.
     
    #17 Mendel Leisk, Jun 8, 2018
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  18. Salman Tariq

    Salman Tariq New Member

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    I'm having same issue with my 2010 Toyota Prius. Engine Light comes on after few weeks and then off again after a week. Car does misfires when light comes on but other that it's been running absolutely fine.
    Got air filter and spark plugs changed. Checked EGR and it wasn't dirty at all but mechanic still further cleaned it.
    I get same code EGR insufficient flow detected.
    Mechanic is saying EGR has a motor most likely EGR needs to be changed but confused. Car runs fine as this issue gas been going on for last 3 months now.

    Please advise

    Thanks





     
    #18 Salman Tariq, Dec 12, 2019
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