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Check engine light on sometimes. EGR valve. Should I replace?

Discussion in 'Gen 3 Prius Main Forum' started by Mnext02, Nov 11, 2019.

  1. Mnext02

    Mnext02 Junior Member

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    My check engine light is on sometimes and then it will go off for a while and then I’ll come back on so I took it in to dealer, they told me my EGR valve needs to be replaced cost of the part was like $380 and then like another $400 in labor so like 775 out the door should I do this? My local mechanic told me I shouldn’t do it, he says it’s not affecting anything other than when I need to get smog done I should have it fixed or something but my MPG is down it used to be around 50 mpg now around 45 mpg. Car has 195k miles and is a 2010. I’m wondering if this has any effect on mpg? The quote was from the dealer do you think I should replace this? I also remember reading somewhere this may be under warranty?
     
  2. bisco

    bisco cookie crumbler

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    more likely it needs to be cleaned. along with the rest of the circuit

    get it done before you blow a head gasket

    does she burn any oil?
     
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  3. Mnext02

    Mnext02 Junior Member

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    yes she burns a lot of oil too. Related? So I should have this replaced in your opinion?
     
  4. Mnext02

    Mnext02 Junior Member

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  5. bisco

    bisco cookie crumbler

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    you can't tell if it needs replacing until you clean it. you should definitely clean it, along with the rest of the connected piping and intake manifold.
     
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  6. Mnext02

    Mnext02 Junior Member

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    I’m having it replaced.
     
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  7. bisco

    bisco cookie crumbler

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    okay, but if they don't clean the rest of it, you're going to wind up with the same problem or worse
     
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  8. bisco

    bisco cookie crumbler

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    there are lots of egr threads here if you want to search, research, and verify
     
  9. Raytheeagle

    Raytheeagle Senior Member

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    Whose the local mechanic?

    Have they ever cleaned the egr circuit?

    You’ll need to do the whole thing to gain any lasting effect.
     
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  10. Mendel Leisk

    Mendel Leisk Senior Member

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    @Mnext02 the operative phrase is "car has 195K miles". Do yourself a favour and listen. The dealerships are clowns, tag along with them and you will end up seriously out-of-pocket, and no closer to dodging a blown head gasket. More'n likely all you've got to do is clean (not replace) all the components that comprise the Exhaust Gas Recirculation circuit. That's everything yellowed in this picture:

    upload_2019-11-11_16-48-14.png

    The exhaust gases are meant to flow through all the yellowed components. The rightmost item is the cooler, and is likely to very clogged by now. Ditto for the small passageways in the intake manifold (lower left). Replacing just the valve (outlined in red) is useless; they system will still be clogged. Accordingly the engine runs hot, and you're in danger of a head gasket failure, which in turn can lead to bent piston arms.

    Simplest and best approach is to DIY, if at all possible. Next best, work with an independent mechanic. You might even be able to find one that'll do the wrenching, let you clean the components: It's also advantageous to install an Oil Catch Can, while the intake manifold's off.

    The simplest way to see where you're at, is to check the degree of carbon build up in the EGR pipe, a stainless steel connecting pipe between the EGR valve and intake manifold. Watch @NutzAboutBolts video #16 here:

    Nutz About Bolts Prius Maintenance Videos | PriusChat

    Two or three other videos linked there too, for the full cleaning of the intake manifold, full EGR clean, and Oil Catch Can install.

    Good thread:

    EGR & Intake Manifold Clean Results | PriusChat

    Another:

    Oil Catch Can, Eliminate that knock! | PriusChat

    Some tools worth having:

    E8 Torx socket (mandatory)
    E6 Torx socket (optional, but good to have, to remove the throttle body studs from intake manifold)
    3/8" ratchet wrench, regular and long handle, flex head, you can never have enough (or 1/2 plus reducer)
    1/4" ratchet wrench, or 3/8" to 1/4" reducer
    Ratchet extensions: you can never have enough
    Long needle nose piers, straight and bent tip
    Ratcheting 12mm box wrench (optional, but makes disconnection of the EGR cooler from exhaust easier)
    Torque wrench (3/8" and 1/4" both good to have)
    Floor jack and safety stands (or ramps): basically some method to raise front, if you need to take underpanel off, which you may need to, both for access and to recover dropped items.
     
    #10 Mendel Leisk, Nov 11, 2019
    Last edited: Nov 12, 2019
  11. hill

    hill High Fiber Member

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    so .... sketchy advice from the local mechanic as well as the OEM service center. Hopefully that $400 includes cleaning out the ancillary components. Otherwise it would be like getting a new heart valve - even though their aorta is plugged up with plaque & cholesterol. You'd be back in the hospital in no time. The sad part is you've got the car cracked open that far anyways, when it's the easiest to do.
    .
     
    #11 hill, Nov 12, 2019
    Last edited: Nov 12, 2019
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  12. Mnext02

    Mnext02 Junior Member

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    Well I got it done. Yesterday I got 48.8 mpg in 150 miles of driving. Today I got 51.4 mpg in 140 miles of driving. This was about 70% freeway. So my mpg is definitely back to where it used to be. Glad I got it done!
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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  14. Mnext02

    Mnext02 Junior Member

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    Today I only got 46.6 mpg in 160 miles of driving. Yesterday I got 51.4. Wth?!
     
  15. bisco

    bisco cookie crumbler

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    driving and weather conditions
     
  16. Mnext02

    Mnext02 Junior Member

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    Same driving same weather. It’s L.A. weather never changes
     
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  17. Mendel Leisk

    Mendel Leisk Senior Member

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    You cleaned the EGR. How was it, how clogged? You were able to clean the cooler pretty good? Intake manifold cleaning, how'd that go?
     
  18. Azlandshaper

    Azlandshaper Junior Member

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    Read closely

    sounds like it was done down the road at a mechanic.
     
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  19. dig4dirt

    dig4dirt MoonGlow

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    What did u get done? Did you have the wallet flush done?

    Did you not heed all the replies that the long time prius owners/members gave you?

    Every reply was letting you know the doing part was cleaning out the components.