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Bad injectors?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by henry ortiz, Sep 20, 2024.

  1. henry ortiz

    henry ortiz Junior Member

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    Hey I have a prius 2010 3 days ago I was driving back home when the engine started to shaken roughly and lost power so I got home and I put the scanner and the code was p0301 misfire cylinder number 1 so could be the head gasket? Mmm…
    I replaced the head gasket gasket 2 years ago and only pass 27k miles since so… I have to tested so I put pressure in the cooling system and with the boroscope see inside the cylinder for any leaks after an hour no loosing pressure and no leaks
    And the piston is not clean but the spark plug is wet and smells a gasoline.
    All 3 cylinders looks good
    I tested the sparks plugs and works fine
    Coils tested and are good
    I cleaned the EGR valve and the cooling system
    Intake manifold cleaned and put a new PCV valve
    Oil catch can is half inch of oil
    So started the car and nothing changed
    And same code p0301
    Back to the cylinder number 1
    And again the spark plug is wet with gasoline
    I checked the others sparks plug and are dry
    So the problem is number 1 wet (gasoline)spark plug
    So I removed the injectors and tested the resistance and the 4 injectors was 12.4 and all of them
    QUESTION???
    • So which the normal resistance?
    • 12.4 resistance are bad? And need replaced for new ones?
    • or can I send them for a service and restoration I don’t know if is wort it?
    Thanks in advance
    Henry
     

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  2. ChapmanF

    ChapmanF Senior Member

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    A fuel injector has an electromagnet coil (which has a resistance), and it has a moving valve (which could stick, and not fully close or fully open), and it has a nozzle (which can partly clog and spray fuel in a poor pattern instead of good fine droplets).

    Measuring with an ohmmeter will tell you if the electromagnet coil has gone bad, but that doesn't seem to be something that happens a lot. It won't tell you about the other things that can go wrong. The tests that an injector restoration firm will run would tell you more. They'll test how much fuel flows, and the spray pattern.

    The wet spark plug in cylinder 1 could be a clue to a cause, or just be an effect. Maybe the injector is sticking open and admitting too much fuel, and that's why the cylinder misfires and the plug is wet. But then, maybe that cylinder misfires for another reason, and the plug is wet because the fuel didn't burn.

    What happens if you swap cylinder 1's injector with another cylinder's?
     
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  3. henry ortiz

    henry ortiz Junior Member

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    Thanks for the explanation I really appreciate it
    Let me swap the injectors
    And how about the measuaring ohms 12.4 is good?
    What’s the standard?
    With those numbers ohms its worth it to send for restoration I see a couple companies offering that service
    Thanks
     
  4. Tombukt2

    Tombukt2 Senior Member

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    You can buy remanufactured injectors from these places that do this kind of work there's one right up the street from my house called diesel something another they work with fuel injectors predominantly for diesel trucks Yes I get it but they have a full setup and can do whatever they want with injectors of almost any type plastic toy ones like we have the big fancy metal rebuildable ones like large machineries have so there's always that I bought a set of remanufactured injectors cleaned with pictures of the pattern and a bunch of specification and numbers and all that nonsense for like I don't know $70 from a pretty seemingly reputable outfit made no difference on my car but that doesn't mean anything really I had the car apart $300,000 mi on it I felt a set of cleaned up injectors could only help matters not really hurt anything didn't seem to help with anything I was doing but like I say at least they should be back to near factory clean specifications like they started out 300,000 miles ago or whatever we're on these when they got dealt with they didn't do mine this was another complete set same color same set same numbers all that Just clean didn't make any difference in my mileage or the way the car ran that I could tell I wasn't chasing a wet cylinder or anything like that this was just happening on the cleaned up persona engine. And that high mileage on any of these other vehicles I would do it again I just put a set on a generation two about a month ago It's a car I drive almost daily and 300,000 plus miles with questionable fuel all its life here in the southeast United States It just makes sense to me to make sure the engine is getting fueled with a decent pattern and amount of fuel when it is running. And these plastic injectors they kind of worry me All this heat now under these engine bays and what have you You got to be kidding But hey I guess these polymers can stand it.
     
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  5. ChapmanF

    ChapmanF Senior Member

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    11.6 to 12.4 Ω is the spec, when the temperature is 20 ℃. That's probably just fine.

    Keep in mind that measuring the ohms in the first place only tells you one thing about the injector, and the one thing it tells you is the thing that hardly ever goes wrong anyway. it tells you nothing about the injector's volume flow or spray pattern, which are more often going to matter.
     
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  6. henry ortiz

    henry ortiz Junior Member

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    Thank you so much for the info
    And I think I’m gonna send them for cleaning and testing to the injectors shop (rebuilt)
    I think is the best option for now
    Thank for your help
    Henry
     
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  7. MAX2

    MAX2 Member

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    Have the spark plugs been swapped between cylinders?
    1-4 2-3?
     
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  8. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    What's the miles? If the aforementioned plug swap does not change the code, I'd suspect head gasket failure. Especially if it's anything over 150K. It's a gen 3 "feature".
     
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  9. henry ortiz

    henry ortiz Junior Member

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    Mileage is 281,556 yes you right i thought the same head gasket, but I replaced at 256,780, new sparks plugs, EGR valve, manifold intake , and injectors cleaned, new PCV, new chain, I replaced all gaskets, new bolts (head gasket)
    So I doubt it was the head gaskets so I tested put air pressure on the cooling system and checked the cylinder for leaks with the Borescope and no leaks. pressure was maintained, never lost for about half an hour
    So is not head gasket
    The thing is I noticed cylinder one spark plug is wet with gasoline
    So I suspected could be a injector or a ignition coil
     
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  10. henry ortiz

    henry ortiz Junior Member

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    Yes I swapped and the cylinder one the spark plugs comes wet (gasoline)
     
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