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Crazy misfires on rebuilt 2010 - coil? Injector?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Rrrolfff, Sep 6, 2019.

  1. Rrrolfff

    Rrrolfff Junior Member

    Joined:
    Jun 12, 2018
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    Location:
    Irvine
    Vehicle:
    2010 Prius
    Model:
    Two
    So I got the wonderful time-bombed head gasket issue a few months back (verified cause coolant was low with no other leaks). Had the engine swapped (with a rebuild that supposedly has the new part to stop this from happening again) at 170K...

    1. Since the swap, I get occasional rough start (only a second), then finally got misfires on 1. Also, mileage seems way off (could be cause my average speed is way low due to idling etc). We reset, then got misfires on all 4, and at WOT only sometimes i'd get lurching acceleration. Every time I take it back, it seems to act better (or course). So they swapped coil #1, and bingo, it ran like a champ for 2 weeks. I did run out of gas before all this - so that's a possible cause (injectors sucked stuff up?).

    2. After 2 weeks, it threw misfires on only #2. Again took it in, and they swapped coil #2 (this time just grabbed a 'used' known good one. He also pulled out the injector 2, and looked at it (did nothing).

    Now I'm wondering if its an injector issue (pressures on their service tool look fine)... I threw in some tech-in-a can Lucas injector stuff for this tank, but am thinking about servicing the injectors myself.

    I can't find any Youtubes for the Gen 3 injector swap (though I watched the tech, and it doesn't look all that hard).

    It seems there are two options - pull each injector, get a $14 Amazon injector cleaner kit, n clean em, or get the Official Toyota injector service thing - I found their cleaner can for $20, but can't find the connector part of the kit. Youtube vieos shows the can replaces the fuel pump, n you block off the fuel pump side with a plug supplied. The can's fuel supply runs till its empty n the injectors are clean. This seems super easy, but I can't find the kit number (and I'm on a budget).

    Still also wondering about the coils as they seem to also be a part of this mess - but are a big hassle to swap out (and expensive unless you buy cheap knock-offs - which Amazon reviewers tend to have issues with).

    Any help or opines are greatly appreciated!
     
  2. The Critic

    The Critic Resident Critic

    Joined:
    Oct 28, 2005
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    Location:
    CA
    Vehicle:
    2011 Prius
    Model:
    Three
    I am a little suspicious of this "rebuilt" engine, especially since the misfires are returning on cyl 1 and 2. Since we do not know why this engine was originally rebuilt, we do not know if the engine was a good candidate to be "rebuilt."

    And by "rebuilt," did they just replace the HG? Or did they go thru the bottom-end as well?

    Knowing how these engines typically "fail," there could be bottom end damage that was missed during the rebuild. Especially bent connecting rods due to hydro locking.

    I would do a compression and leak-down test of the engine before putting any parts into it.
     
    Raytheeagle and Rebound like this.
  3. spiralhelix

    spiralhelix Active Member

    Joined:
    Mar 15, 2019
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    Location:
    Illinois
    Vehicle:
    2011 Prius
    Model:
    Three
    i agree with Critc's response. I'll address the injectors. They are stupid easy to replace since they are right there easy to get at. A few things should be removed to make it easier. but once you pull the rail, they can just be pulled out. Some engines suck to work on, for the most part, this is one of the easier ones! I personally wouldn't waste money on an injector kit thingy (not sure what it is tbh), I just took a small section of fuel line (maybe 3/8, can't remember), blocked off one side with a bolt glued in with gasket maker (because it was in front of me at the time), then poked a hole in the side slightly above where the injector would end when the line was pushed in, and stuck in the red straw for a spray can. Now you can add carb cleaner to the injector without stuff flying everywhere. Then with a couple jumper wires and a momentary push button and a battery, you can spray the can, push the button quickly which will open the injector, and watch the junk explode out like a...

    Turn the injector around in the hose, and do the same (reversing the flow of cleaner). that's all she wrote. Some would say go backwards first just so you don't push more junk through the injector. Eitherway, you're gonna clean it.
     
    Rebound likes this.