after 4 new plugs and an injector . . . .

Discussion in 'Gen 2 Prius Main Forum' started by lexidium, Oct 10, 2025 at 2:05 PM.

  1. lexidium

    lexidium Active Member

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    Had a slight misfire on cylinder one so fitted a new injector and changed the four plugs at the same time.
    Now it runs ok for a while and then rattles and wobbles when coming to a stop. It showed obd code P0420.
    If I switch it off and on again, it then runs fine for a while but then happens again.
    Any suggestions?
    Thanks guys
     
  2. bisco

    bisco cookie crumbler

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    what does that code stand for?
     
  3. bisco

    bisco cookie crumbler

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  4. BiomedO1

    BiomedO1 Senior Member

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    what was the reasoning behind changing the injector? How did you determine it was an injector fault?
    did you troubleshoot the misfire and/or did you get a P0301?
    how did the plugs look when you pulled them out?
    how many miles/km on the clock?
    how much oil burn between oil changes and at what interval?
     
  5. lexidium

    lexidium Active Member

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    Yes. Had p301 so I changed the coils over and spark plug looked ok but fitted a new one anyway and misfire was still there.
    175,000 on the clock.
    oil is fine
     
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  6. BiomedO1

    BiomedO1 Senior Member

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    did you do a compression test or look at fuel trims before replacing the injector? Did you do all 4 or just one injector?
     
  7. Aegean

    Aegean Active Member

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    Do you think engine temperature, when car is warm or cold changes anything? Or when idles you have the issue and when driving with higher rpm is working fine?