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Prius engine is rattling and hesitating...

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by johnso21, May 21, 2019.

  1. johnso21

    johnso21 New Member

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    So I've done just about everything I can think of to maintain this vehicle and I'm about ready to drive it to the dump. I love it to death but lately I'm frustrated. I've had it since 2012, its a 2010, and I bought it with 72k miles on it. It has 212k on it now.

    It started one day with the rattle that seems common on startup, it lasts about 20-30 seconds then seems to be fine. Then after a while it extended to when I put the engine under load going between 20 and 30mph. Needless to say this was disconcerting. So I went crazy with maintenance.

    I've done the following:
    Oil Change/New oil filter
    Added seafoam to the oil as well as ran two seafoam treatments through the gas tank
    Changed the transmission fluid
    Changed the engine coolant
    Changed the inverter coolant
    Changed rotors and brake pads (i know this has nothing to do with the engine noise but the point is I maintain everything as good as I can)
    New PCV valve (done about 7.5k miles ago)
    Completely took out the intake valve and throttle body and cleaned them to death
    Installed oil catch can (around 3k miles ago - and yes it is catching oil although not a super crazy amount, so far the catch can is about 1/4-1/3 full)
    Removed and cleaned the EGR Valve
    Removed and cleaned the EGR Pipe
    Removed and cleaned the EGR Cooler
    New spark plugs were installed about 7.5k miles ago

    After all this the engine rattle/sound of death is still present...could it be..? what? Ignition coils? Idk. I'm not a mechanic but I do all the work myself and do enjoy it but when it seems there is no improvement whatsoever...and I just want to drive it through the wall of a toyota dealership... lol (not really actually do that but I've done it in my mind the past day or so).

    Any suggestions? Help..

    Edit: I also have an OBDII scanner, I've scanned this car constantly and it hasn't thrown any codes... I do live monitoring as well and the scans come back fine...I wish for once a stinking check engine light WOULD come one for once.
     
  2. johnso21

    johnso21 New Member

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    I also was just about to order new shocks/struts today as well as the main engine mount just because...probably not gonna order any of that now because Im getting ready to trade this car in. :(
     
  3. tankyuong

    tankyuong Senior Member

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    If it’s using coolant then you have a blown head w
     
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  4. orenji

    orenji Senior Member

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    How long ago was the EGR cleaned?
     
  5. johnso21

    johnso21 New Member

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    I’ve been watching the coolant level. It’s not changing or dropping.

    EGR was cleaned this last weekend. I cleaned the EGR valve and the EGR pipe and EGR cooler all at the same time. All the maintenance work I’ve done has been in the past few weeks except spark plugs and PCV valve.
     
    #5 johnso21, May 22, 2019
    Last edited by a moderator: May 22, 2019
  6. The Critic

    The Critic Resident Critic

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    I hate to be the jerk, but I would not have done all of that maintenance in an effort to correct the issue. Maintenance is supposed to reduce a vehicle's cost of ownership; it is rarely a method of repairing an actual problem.

    It seems like you have addressed the EGR circuit and the intake manifold (I suppose you meant intake manifold and not intake valve).

    Based on your mileage and the model year, it is very likely that this is a head gasket issue or will be soon. If you want to verify, I would do a leak down test; this should be reveal if you have a failed head gasket.

    Otherwise, I would make sure the EGR is fully functional (I assume you disassembled it and cleaned ALL of the carbon) and make sure the engine software is up to date.

    Trading it in is not a bad idea if you are not financially prepared for a major engine repair; it is probably in your future at this point.
     
  7. johnso21

    johnso21 New Member

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    Not a jerk at all. Maintenance needed to be done anyway so while I was cleaning the EGR system I did everything else at the same time. Makes sense right?
    If I’m not losing coolant can that shuddering still be blamed on a head gasket issue?
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

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    With 212K miles on, and assuming the intake and EGR clean out was only done recently, when rattle/shake symptoms started, I'd suspect the protracted period of driving with clogged EGR/Intake (with elevated combustion chamber temps) has done in the head gasket.

    How's engine coolant reservoir level?

    Do a leak-down test?

    Inspect with boroscope, looking for coolant?
     
    #8 Mendel Leisk, May 22, 2019
    Last edited: May 22, 2019
  9. Mendel Leisk

    Mendel Leisk Senior Member

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    I think so, but I'm definitely a denizen of the shallow end of the mechanical pool. The head gasket is instrumental in keeping both coolant and oil passages from leaking, and also to keep the cylinders from leaking, either to the outside, or into eachother, or into the coolant/oil passages. Depends on where the gasket fails.

    Maybe someone with more smarts can elaborate, list the symptoms.

    Compression test and Leak-down test would shed light.
     
  10. johnso21

    johnso21 New Member

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    Ok so update...I’m confident it’s not a blown head gasket. I checked the oil and coolant. Everything looks good...but...I opened up the catch can and smelled the “oil”. Smelled like it was cut with a decent amount of gas. I also put her in maintenance mode and went and sniffed the exhaust. Very gassy. I took a video of the chunk a lunk clunk clunk sound...I’ll add a link to the video.
     
  11. johnso21

    johnso21 New Member

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    This is the video I just took. Warning: this video contains sounds that Prius lovers may find disturbing...
     
  12. Mendel Leisk

    Mendel Leisk Senior Member

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    I think it's normal for Oil Catch Can content to be a "strange brew", especially this time of year, coming out of winter. I would still consider compression and leak-down tests, not sure you're out of the woods.
     
  13. johnso21

    johnso21 New Member

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    Perhaps the most frustrating thing in all of this...is that I've had the car for 8 years and 165k miles...its 10 years old and has 214k miles...and I've never seen it throw a CEL...
     
  14. johnso21

    johnso21 New Member

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    Ok...i'm gonna take it in and have someone do that. I dont think its something I can do in my garage...
     
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  15. Raytheeagle

    Raytheeagle Senior Member

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    So the coolant level is stable and you’ve been monitoring it?

    Our 2010 that I just sold last month made that racket once and that was after sitting at the Oakland airport for 10 days:cool:.

    I’d ensure the level is stable before you write off the head gasket as fine;).

    Good luck and keep us posted (y).
     
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  16. johnso21

    johnso21 New Member

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    It is very stable. I commute about 150 miles per day and I've never once had to add coolant. I do check it daily, at least I have been since saturday.
     
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  17. tankyuong

    tankyuong Senior Member

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    Mine made that noise when I put ebay counterfeit Toyota plugs, switched them out for ngk from oreillys and it solves the problem
     
  18. Center of Gravity

    Center of Gravity Junior Member

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    I have to go with Tank on this. This is definitely not a head gasket issue, and is more of an out-of-balance firing on Startup and Shutdown. From watching the video and I have to watched it again, and again and I get the sense it's on Startup and Shutdown only so it's more of a timing of spark advance and getting knocking do to misfiring. If you got the cash then change the plugs and spark plug wires or just inspect the wires and see if one is misfiring to the block i.e. has a crack in it or something shorted to the block/valve cover...

    Once the engine starts and you are driving down the street do you still get the misfire or feel it or hear it ticking sound? Another trick test would be to do it at night in the garage with all the lights off and see if you see additional sparks coming from the spark plug wires to the surrounding metal.

    If you are not getting a misfire code when you do code checks then this is not misfiring in a severe sense, but could still be there on startup and shutdown, and the ECU is not registering it

    Posted via the PriusChat mobile app.
     
  19. johnso21

    johnso21 New Member

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    So you guys were spot on, it is NOT a head gasket issue, i was skeptical that it was too since there was no coolant loss at all, and the oil was super clean. It was a misfire of cylinder 4 due to the intake manifold...so i replaced the intake manifold with a new one (apparently there is an upgraded one they put out in 2012), put it in and now she runs like a dream. Wasn't expecting that since I had just taken out the old intake manifold and cleaned it (apparently not well enough).
     
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  20. FED

    FED Junior Member

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    i have a similar issue. I see your solution was to put a new intake manifold. But you mention misfire of cylinder 4. And in my car I dont read any error code misfire on any cylinder. please help. thank you.