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Misfire help needed

Discussion in 'Gen 3 Prius Technical Discussion' started by Michael48, Mar 25, 2018.

  1. Michael48

    Michael48 Junior Member

    Joined:
    Dec 13, 2016
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    Location:
    Seattle
    Vehicle:
    2012 Prius
    Model:
    Two
    My 2012 Prius started rattling like they do and it was something that would go away.. Then I had my temp light come on and I drove car home after stopping many times and filling the coolant up. Seems my water pump had frozen. Replaced the water pump and started the car, Now it rattles almost continuously. I can rev it up sometimes and get it to accelerate.
    At other times, I push the pedal and no increase in engine rpms. I scanned and found a P0302. Since its my daily driver (160,000 miles in 3 years) yes 160,000, I haven't had to do much. I replaced the plugs, coils, and number two injector and it almost seemed to get worse with the new injector. Could be my imagination at this point. After putting it all back together, I tried to get it to accelerate while i was still in driveway and the engine backfired, something I have never heard before. I did notice when pulling the fuel rail that I didn't get a spray of fuel pressure after unbolting it. I pulled the efi fuse before I did this but I feel there still should have been some pressure. I want to test my fuel pump pressure but don't know how to connect the gauge since I can't get the quick connect apart at drivers side of engine. Is there a secret to this? I'm cleaning everything (egr, cooler, intake manifold, maf sensor, bypass tube, etc. so this will be my last try.
    I have gotten to know my Prius deeply now and find it very easy to work on. Water pump in 20 minutes, plugs and coils 30-40 even with the cowling having to come off. Egr cooler and egr valve didn't take long either. Now if only I can get this dumb fuel line connector apart. Any ideas?
     
  2. Aaron Vitolins

    Aaron Vitolins Senior Member

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    Franklin TN
    Vehicle:
    Other Hybrid
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    Hey Michael, unfortunately it's the more and more common headgasket problem. You can search headgasket on priuschat and see all the posts on the issue. My sisters prius (a 2010) did the same thing. We tried everything hoping it wasn't the headgasket. But it was, and this was before a ton of these issues came to the table so if it had Happend now, we would have never even replaced so much, and wasting so much money.

    Since her car drank oil too we bought a used low milage engine to replace it with.
     
  3. Michael48

    Michael48 Junior Member

    Joined:
    Dec 13, 2016
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    Location:
    Seattle
    Vehicle:
    2012 Prius
    Model:
    Two
    This has been a great car and now has 207k on it. Everything except the egr looked ok but the missing fuel pressure spray is the only thing at this point that is keeping me from getting another engine. I have the tester, just need to know how to connect it. Never used oil, always up on stick. Thanks for replying ... I have already scoped out a couple of replacement engines just in case.
     
  4. Aaron Vitolins

    Aaron Vitolins Senior Member

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    Other Hybrid
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    Well I'm glad to hear it isn't buring oil! Especially with that amount of miles. Yeah since you've gotten this far you might as well check the fuel pressure.

    Have you noticed any coolant loss?

    Also do you know which cylinder is misfiring ?
     
  5. Michael48

    Michael48 Junior Member

    Joined:
    Dec 13, 2016
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    Location:
    Seattle
    Vehicle:
    2012 Prius
    Model:
    Two
    P0302, cylinder 2. No coolant loss. Replaced number two injector along with all new plugs and coils. FYI, i have a verizon hot spot in my car made by delphi, which also allows me to monitor my car for codes, alerts, voltages, etc. Its a handy way to scan and clear codes in case anyone is interested.
     
    Aaron Vitolins likes this.
  6. Michael48

    Michael48 Junior Member

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    Location:
    Seattle
    Vehicle:
    2012 Prius
    Model:
    Two
    Well, figured it out on my own. This little baby did the trick. Lisle connector tool #39410 - Now to figure out how to test the system.
     

    Attached Files:

    mjoo and Danny3xd like this.
  7. Erik Owens

    Erik Owens Member

    Joined:
    Mar 25, 2018
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    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Three
    Check out TSB-0116-15 REV1. There is a TSB for the intake assembly. Something with the EGR passage internal to the intake.