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Clatter noise at startup. Heads up

Discussion in 'Gen 3 Prius Technical Discussion' started by harry r, May 15, 2012.

  1. harry r

    harry r slowly turning green

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    Just a heads up. Started my 2010 gen 3 Prius 3 the other day and got a bunch of what I thought was engine clatter and the check engine light came on. Called the Toyota dealer, they said bring it in when I get a chance. The next time I started it, no noise. Anyways brought it to them and they diagnosed it and ordered a new manifold. The next day when the part arrived, I brought in the car. Talked to the mechanic, a great guy, and he explained what happened. Apparently, the clatter is actually the springs rattling in the clutch mechanism of the starter motor/electric motor and not the valves like I thought. Anyways, the mechanic stated that Toyota figured out that sometimes oil accumulates in the manifold somehow causing the noise. Sorry I forgot exactly how the oil creates the noise. But in any case, they ordered a new manifold and installed it in 1.5 hours. The mechanic said this is the first 2010 he has had to do this too but apparently, it's not unusual in past priuses. Apparently, Toyota has been tweaking the manifold to get rid of this because the manifold is actually on the side and below the engine allowing the oil to seep in there.

    I hope this helps, it was news to me but glad for the relative easy fix and Toyota stepping up quickly, even with a loaner.

    Oh by the way, it was a technical service bulletin per the service writer so it's on their radar.
     
  2. spiderman

    spiderman wretched

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    Thanks for the update. But I don't think your service guy got it right. There is no oil in the intake manifold. What we were told was it was water/condensation build up in the manifold that would get sucked in during startup causing the misfires. The new manifold now has ridges that trap the water until is vaporizes later.
     
  3. harry r

    harry r slowly turning green

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    Not sure what to say. He is a Prius owner and explained what he does to his car occasionally to remove the issue ohis intake manifold. He seemed very knowledgable. In any case lets hope it takes care of the problem what ever is was.

    By the way the sound I heard was not a misfire.. It was definitely metal on metal and that was not good. That tends to support his explanation that it was the clutch springs.
     
  4. spiderman

    spiderman wretched

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    And that very well be where the clanking noise comes from (dampener) but the cause is the misfire. In fact many members here reported the error code (engine light) misfire.

    Like you said, hope that fixes it. Be sure to chime in again if it does.

    I had mine replaced in March and hope I never hear it again!
     
  5. harry r

    harry r slowly turning green

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    I hear ya on never hearing that sound again. By the way, funny thing is while I was talking to the mechanic, he tried to sell me on an extended warranty..lol. Made me a bit nervous but again I decided its a Toyota so no Tks. Let's hope that bet works out..lol
     
  6. David Beale

    David Beale Senior Member

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    Well, you can get oil in the intake manifold, due to the Atkinson cycle "blowing back" some intake charge. This is why on the GII one thing lots of owners do is clean the intake manifold and MAF sensor.
    It appears to me, reading this, that Toyota is still trying to fix this "clatter" issue, which is ongoing. Do a search and you'll find lots of posts from panicked owners. So a redesign of the intake manifold was done? Interesting. I wonder how many owners will get the new manifold.
     
  7. cobra427

    cobra427 New Member

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    can anyone help i have a 06 prius on start up all is ok when engine fires up i get a rattle a bit like a clutch rattle, this happens when it is charging ie the display show arrows from motor to elec motor to battery. the minute the engine is not charging and the engine is just idling ie no arrows on display the noise goes. it also only makes this noise in p mode every thing is working fine no fault codes nothing any ideas
     
  8. cwerdna

    cwerdna Senior Member

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  9. cobra427

    cobra427 New Member

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    im afraid my prius is long out of warranty why does the clatter noise go when i select any other mode apart from park instantly i have been to the dealers here they give me a vague look kinda scary im sure they know whats going on, is it a costly fix??? prius has done 90.000km
     
  10. gsodonis

    gsodonis Recent Hybrid Convert

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    We bought our 2012 3 HB In March of this year. Twice in May on different mornings (temperature both nights in the 60's) we heard a momentray mettalic clatter for a few seconds at startup. No CEL either time. I've heard the condensate caused knock and it cenrtainly wasn't it (it wasn't cold enough outside). It hasn't happened since and I hope it doesn't happen again but I'll keep posting if it returns.
     
  11. David Beale

    David Beale Senior Member

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    The clatter noise in the GII is not part of this topic. It's not "normal" or common in the GII. In fact I've never heard of it. Are you referring to engine start-stop? If you put heavier motor oil in the engine it will "hunt for position" when stopping and be a little rough when starting. Make sure you are using 5W30 or so.

    If that's not what you're experiencing, there is a "clutch" in the power train, used to limit torque impulses. Perhaps that's failing? It's a fixed clutch, with no release mechanism. It just slips when the drive is over-torqued. Though if it only happens in "P" I don't think that is it.

    Does the transmission lock in "P"? If not, then the "park lock" mechanism has failed.
     
  12. Metalman

    Metalman Member

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    We had a terrible clatter at start up after the 2010 Prius sat for five months in a non heated garage, under the house. The temperature never drops below 40 degrees. The engine was stopped and restarted and the chatter lasted only a couple of seconds. The engine was shaking terribly and I assumed it was running rough because it hadn't been run for five months. The next time it started it clattered for a second and no more clattering after. Should we contact the dealer about it?
     
  13. David P.

    David P. New Member

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    Hello everyone! My first post here. So, is this something to be concerned about, this very brief clatter noise on start up? If it’s just a slightly alarming sound that goes away quickly, but doesn’t mean that the engines going to be damaged or have any problems, maybe I don’t need to have anything replaced. What do you think guys? And girls?
     
  14. AzWxGuy

    AzWxGuy Weather Guy

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    Hello, and welcome to PriusChat. What you might be hearing is a 16 valve tappet chorus resulting from a drained-of-oil distribution pipe, maybe resulting from a stuck back-flow valve. I don't know for sure if your engine, or even my engine, has a valve like this to keep the upper oil gallery from draining. I think some sort of back-flow prevention used to be incorporated into the spin-on oil filters, which are no longer allowed. Someone else in the know may chime in about these symptoms. Or maybe there is a Prius V group with better answers higher up on the PC front page than Gen III? I don't look around much.