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P0a0f, p0302, p2195, p3190 - After replacing plugs, coils, crankshaft and 02 sensor

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Jimmy Latta, Nov 8, 2023.

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  1. Jimmy Latta

    Jimmy Latta New Member

    Joined:
    Nov 8, 2023
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    Location:
    oklahoma
    Vehicle:
    2007 Prius
    Model:
    Four
    Hello,
    I am working on a 2007 Prius. I rebuilt the main battery pack earlier this year. We later started getting codes for the inverter pump and coolant control valve along with a 02 sensor error. I replaced those a couple months ago. Continued to get an error with the 02. (I didn't realize upstream went by a different name). We kept getting an error saying it was the hot coolant reservoir, but we noticed the coolant was still low. I topped it off several times thinking I didn't get all the air out. I later put dye in and traced it coming out of the overflow on the coolant storage tank. It has always had a little rough shutoff/start when at lights. To prepare for an upcoming trip I went ahead and replaced the other 02 (upstream - aka fuel ratio), plugs, coil packs and fuel injectors. That night it ran a little rough but nothing to raise any flags. The next day i went to a store 1/2 mile from home and it died on the way back. It was giving me a p3190&p0a0f error. By this point, idling sounded like an angry rock tumbler. To troubleshoot, i replaced the coils and plugs with the old, then back to the new... then the old injectors back to the new. Still sounding horrible, I went ahead and replaced the crankshaft sensor at this point. Although it no longer sounds like everything clanking around, it still idled rough. After about 5 minutes of idling, it died again giving me errors - p0302, p2195, p3190, p0a0f. It will not go into drive, but was able to put it in neutral. I will move the cyl 2 plug and coil to another position to see if there is any change. IF not, am I correct to assume that it may have blown a head gasket?

    2007 Prius - Touring (leather)
    almost 300k miles

    Thank you
    (i'll see if i can upload short video clips from my phone later)
     
    #1 Jimmy Latta, Nov 8, 2023
  2. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
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    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    Hello & welcome to PriusChat!

    A bad Head Gasket is certainly possible. My usual process is to pressure test the cooling system to 13 psi (a special pump replaces the radiator cap). Then take the spark plugs out and look inside the cylinders with a videoscope - a scope with a 90° side view really helps.

    That said, a bad H/G by itself usually does not cause a hard (constant) misfire. A small amount of coolant leaks into the cylinder overnight, then fouls the sparkplug & causes a miss on startup. The cylinder "clears" the coolant then runs ok until next cold soak.

    IF there's a "large" coolant leak then the cylinder can hydrolock and bend the connecting rod. That causes low compression, misfire, and eventual rod failure and hole-in-the-block.

    Right now you do not KNOW much. Two codes are "hey, the ICE (engine) isn't running properly". There's the misfire code. P2195 (upstream A/F sensor reports lean) could be the cause of the miss, or it could be the result.

    You have swapped a bunch of parts around. Ok. Lots of times, that's enough. But not here. You will need to do some tests. First would be engine compression. This requires a decent State of Charge in the HV battery, a compression gauge (set), and a scantool that supports this function. Even with that it can be a bit "fiddly" to correctly follow the prompts on the scantool and complete the process.

    If compression is even with other cylinders, then you would need to determine if the injector and ignition coil actually work - not everyone can (safely) do this level of testing.

    Posted via the PriusChat mobile app.
     
    #2 mr_guy_mann, Nov 9, 2023
  3. Jimmy Latta

    Jimmy Latta New Member

    Joined:
    Nov 8, 2023
    7
    0
    0
    Location:
    oklahoma
    Vehicle:
    2007 Prius
    Model:
    Four
    Sorry. Been out of town a few days.

    Update-. Swapped plug/coils on cyl 2&3. Since misfire was on 2. Other errors went away but. . . But now showing a misfire on cyl 1 (p3191) and p0a0f (from it dying).
    I didn't touch cyl 1 or 4 when trouble-shooting today.
     
    #3 Jimmy Latta, Nov 12, 2023
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