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Plastic Engine Cover: Why Keep It?

Discussion in 'Gen 3 Prius Main Forum' started by Rebound, Jul 18, 2017.

  1. Rebound

    Rebound Senior Member

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    The Prius has an easily removed, silver-colored plastic cover on top of the valve train. Does this plastic serve any purpose other than appearance?

    Could the engine cooking be slightly improved by removing it? Any disadvantage to keeping it off?
     
  2. StarCaller

    StarCaller Senior Member

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    that was my thought, too/
    now my cover sits on a shelf in the garage....
    but there are for sure some people here who swear that nothing what toyota does is without ne useful sense.... ;):)
     
  3. StarCaller

    StarCaller Senior Member

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    that was my thought, too/
    now my cover sits on a shelf in the garage....
    but there are for sure some people here who swear that nothing what toyota does is without ne useful sense.... ;):)
     
  4. StarCaller

    StarCaller Senior Member

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    that was my thought, too/
    now my cover sits on a shelf in the garage....
    but there are for sure some people here who swear that nothing what toyota does is without ne useful sense.... ;):)
     
  5. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    I vote no. However:

    If you take it off you'll more'n likely lose it. IIRC, I remove it every time I'm adding oil. That's basically at oil changes, I've never needed to top-up, knock on wood.
     
  6. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    New posting technique, to avoid double posting: hit "Post Reply" button, then, regardless of the lack of result, even with page refresh, assume it's posted. Go away, make coffee, spackle the den, come back: it'll be posted.
     
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  7. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Seems back to normal now.
     
  8. jerrymildred

    jerrymildred Senior Member

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    I've wondered about that, too. As far as I can tell, it's just cosmetic. I'll keep an eye on this thread to see if someone has any official info on it.
     
  9. Prius Maximus

    Prius Maximus Senior Member

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    IMHO, the biggest disadvantage to removing it and leaving it off is losing it or getting it damaged in storage. These covers are simply a way to make used cars look better on the lot when you pop the hood. You don't see the leaking oil and dirt.... So when it's time to sell your car, remember to put it back on.

    I don't know anything about cooking with the engine, I've never tried that!
     
  10. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    upload_2017-7-18_10-22-14.png

    Kinda begs the question: where's NO. 1 CYLINDER HEAD COVER, lol.
     
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  11. BZzap!

    BZzap! Senior Member

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    I would guess that, that cover has a purpose other than aesthetics. Most assuredly it aids in dampening valve train and injector noise. On my previous car (Suzuki SX4) the cover was even insolated. To save weight and expense, I don't think Toyota would have used it, if they didn't think it was necessary or effective. Of course I could be wrong but it wouldn't be the first time.
     
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  12. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Yeah there is a small zone with some padding, over some conduits and u identified something or other.

    IMG_7204.JPG
    IMG_7205.JPG
     
  13. bisco

    bisco cookie crumbler

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    on a shelf in someone's garage...
     
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  14. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    The plasticky cover probably doesn't do very much except make the engine compartment look a little better and give the folks at Toyota a nice big placard to place the corporate "crossed bung-hole" emblem onto.

    As far as "cooking the engine" well this is my second thread regarding a poster that is concerned about the engine running too warm, and I tend not to think that this is much of a 'thing' for modern ICE equipped cars, otherwise they would have a different thermostat.
    Remember, it wasn't that long ago that Prius drivers were trying all kinds of zany things to KEEP their engines warm during their first few minutes of flight......because......I'm told that a warmer engine is a cleaner one.
    Ask the people over at Vee-Dubbaya.

    Be that as it may, if the thermostat is opening and closing with the silver plasticky cover thingy in place, then it will not run any cooler with the cover removed.
    Unfortunately, sometimes it can be difficult to tell, because......unlike cars with proper instrumentation, Toyota placed the temperature gauge right next to the tachometer in the Prius, despite the fact that there are three or four ways to display what the car thinks that your fuel economy is at any given time.
    ...and you know what?
    Given the accuracy of the MDF's guesstimate of DTE and Fuel efficiency compared with real-world values calculated at the pump, I don't have any problem with Toyota not putting oil or coolant temp gauges in the car. ;)

    One of the many advantages of rolling a Prius, and probably one of the greatest strengths of the car is that, with any passing attempt at maintenance, the car is pretty rock solid out to about 120-150,000 miles with little chance of a four-figure repair.
    You simply do not have to worry about much - including, IMHO, how warm the engine is running.

    Good Luck!
     
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  15. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Yeah I think it's main purpose, maybe sole purpose, is looks.

    Personally I prefer the functional/unadorned look, but take it off: it will get lost, amongst the detrious of the garage.
     
  16. bisco

    bisco cookie crumbler

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    why do you remove it to change the oil?
     
  17. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    My oil fill funnel seats better, with the cover off.
     
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  18. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    +1.
    I don't change the oil in my company Prius, but it works the same way in my CFO's car.
    I give Toyota due credit for not adding goofy fake intake runners or carbon fiber accents.
     
  19. Raytheeagle

    Raytheeagle Senior Member

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    The Lexus RX450h engine cover is insulated in addition to adding a measure of plastic appeal.
     
  20. Rebound

    Rebound Senior Member

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    Because if you spill a little oil on the plastic cover, it will permanently stain unless you immediately clean it.
     
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  21. bisco

    bisco cookie crumbler

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    bisco hasn't changed his own oil in 32 years.:oops:
     
    #20 bisco, Jul 19, 2017
    Last edited: Jul 19, 2017