Bit of urgent help if possible....

Discussion in 'Gen 3 Prius Main Forum' started by drives, Sep 15, 2021.

  1. drives

    drives Junior Member

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    Hi all,

    I've been doing a few bits on the Prius over the last couple of days (spark plugs, egr cooler and pipe) and I've come to re assemble the bits and I cannot for the life of me figure out where this electrical connector goes...

    So, from the fuse box and then where to??! It's a uk (rhd) vehicle.

    Thanks! 87C1A644-5BA8-476C-A2B9-7DA60E846266.jpeg
     
    #1 drives, Sep 15, 2021
    Last edited: Sep 15, 2021
  2. ChapmanF

    ChapmanF Senior Member

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    What's that plugged onto the end of it? Kind of looks like a blind cap with rubber plugs where the two wires would go?

    If so, it would seem to be something unused, so the 'where' might not be very important.

    In LHD cars, I think something emerges from that same spot on the fuse box and goes to the brake fluid level sensor (which is right above there in LHD cars). Its wires are pink and white-with-black-stripe though, not red and blue.

    You'll get the best answer in the least time if you just look in the UK RHD wiring diagram, accessed as described on this wiki page.
     
  3. drives

    drives Junior Member

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    Thanks Chapman...when I put the bits back together it clearly clips into the undertray that the wiper motor sits on- as in the plastic holding clip. The connector doesn't seem to connect to anything. I found a couple of previous posts in the interim regarding this 'redundant' connector on RHD vehicles- just not sure why I didn't really notice it, when I took it all apart!

    Anyway, main thing is EGR pipe and cooler cleaning done...and my vehicle seems to work fine without it plugged into anything. Happy days!
     
  4. Mendel Leisk

    Mendel Leisk Sand Pounder

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    Did you clean the intake manifold also? It has EGR passages as well. Some info in link in my signature.
     
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  5. drives

    drives Junior Member

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    Erm…didn’t quite get round to that bito_O. Wasn’t quite sure it was as essential as the other two components but will do a bit more reading up.

    I did oil, spark plugs (what a ball ache that is but at least it had the benefit of aiding access for egr cooler), and the aforementioned bits. Annoyingly I thought I was well prepared in buying a second hand EGR cooler off Ebay so I had pre-cleaned it ready to go on, only to find that whichever spanner monkey removed it had contorted one of the mounting plates which was only noticeable when I came to fit it. Cue a rapid de coke and power wash clean of my existing one to get it all done today.



    I've still got a PCV valve to fit so might look into the manifold as well but just glad I got spark plugs and the cooler ticked off the list.
     

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  6. Mendel Leisk

    Mendel Leisk Sand Pounder

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    The intake manifold has the last leg of the EGR, on the way to the intake ports. The stainless steel pipe between EGR valve and iintake feeds the gasses in, they run through a long gallery*, then into capillary branches, one per engine intake port. The capillaries are approximately 1/4" inside diameter, prone to to clog with carbon, and unevenly so: for whatever reason the capillary at cylinder one (rightmost cylinder, at the "front" of the engine, the end with the beltless pulley, opposite end from the transaxle) is the first to clog. Perhaps related: the head gasket failures are commonly happening at that same end.

    In a nutshell: until you clean the intake, in particular those EGR capillaries, the EGR cleaning is largely for naught. The intake cleaning is relatively easy, compared to the EGR valve/cooler. For the capillaries a slim bottle brush is good. I use a brush intended for cleaning stainless steel drinking straws, with brake cleaner.

    Again, the EGR link in my signature has info: video links, tips, Repair Manual excerpts (with torque values).

    * Toyota revised the EGR passages in the intake, perhaps in (North American) model year 2012, from one full width gallery feeding into four capillaries, to a shorter gallery, feeding into two intermediate passages, then the four capillaries. This was to be part of the "cure" for EGR issues, and a few years back they recommended to replace older intake manifolds with this revised intake, if there were problems. They also revised the EGR valve. Both those revisions haven't seemed to make much difference; the only thing effective (in my opinion) is periodic clean-out.
     
    #6 Mendel Leisk, Sep 15, 2021
    Last edited: Sep 15, 2021
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  7. drives

    drives Junior Member

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    Right ok. Thanks for the heads up. I will have a read and maybe tackle it next week. But, good to know I’ve got the griefy bits out of the way. Manifold removal looks pretty straightforward
     
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  8. jzchen

    jzchen Senior Member

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    Windshield heater for wiper park position?
     
  9. drives

    drives Junior Member

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    I didn't know there was such a thing:). I will try and do some more investigating next week and take the trim off again, but my conclusion at the moment is that it doesn't actually plug into anything. Odd.
     
  10. Mendel Leisk

    Mendel Leisk Sand Pounder

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    I think our 2010 has a loose connector in front of the engine and AC radiators; might be for radar cruise (which we don’t have).
     
  11. drives

    drives Junior Member

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    Well I'm glad you gave me this prompt, now that I've done a bit of reading up, as from admittedly dipping in and out of this forum rather than being a regular visitor, I didn't realise the intake manifold was also a prime potential culprit. Thanks Mendel.

    So thin bottle brush, brake cleaner- on the list. Is a new gasket essential?
     
  12. Mendel Leisk

    Mendel Leisk Sand Pounder

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    There are three gaskets on the intake manifold: the main one at the interface between IM and the engine intake ports, one between throttle body and IM, and one at the interface of IM and EGR pipe.

    Replacement of any or all is not mandatory; I didn't change any in the two times I've had the intake off ours, albeit only around 75K~85K kms on the odometer. The all looked fine.

    That said, if you've got significantly more miles, and/or just want the peace of mind, new gaskets are not too expensive. I think the the main one, at the intake ports, is around $30 USD?

    All 3 gaskets at the intake manifold are pliable/flexible material, so maybe a stronger argument to change. That's comparing the the EGR system gaskets, which are plain steel, stainless I think.

    The repair manual* (maybe dogmatically?) says replace all the gaskets, intake manifold and EGR circuit (the steel ones), but I think you can make judgement call.

    * The EGR link in my signature leads to a post with relevant Repair Manual excerpts.
     
  13. ChapmanF

    ChapmanF Senior Member

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    It's a silicone gasket with some depth and resilience to it, so it is more reusable than old-style flat ones. Still, after ten years it can be kind of cooked and less resilient than it was. If you replace it now, the new one will probably stay resilient and confidently reusable for years more.
     
  14. burebista

    burebista Member

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    I replaced two of them because I didn't know about the third one on throttle body. :(
    The one to engine intake ports was flat but still elastic.
    The one to EGR pipe was fine I guess.

    Anyway I've changed both. The engine one was 12 bucks and EGR pipe one around 4 bucks here.
     
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  15. xliderider

    xliderider Senior Member

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    The Felpro IM gasket I got came with the throttle body gasket as well. I didn't replace the o-shaped one between the IM and the EGR pipe.

    Posted via the PriusChat mobile app.
     
  16. jzchen

    jzchen Senior Member

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    Our 2004 Toyota Sienna has this feature. When I had the windshield replaced (due to a crack) I was initially sold one without the heating element. Then I got a replacement with the proper connector that is located right in the center bottom of the windshield, so just about where you noted your loose one ends. If the windshield/(sorry is it windscreen there?) was ever replaced it's possible that one without the heater was used. Then it would be left dangling like that....
     
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