Weird idle noise and struggles to accelorate

Discussion in 'Generation 1 Prius Discussion' started by Mark Anthony, Apr 21, 2025.

  1. Mark Anthony

    Mark Anthony New Member

    Joined:
    Apr 21, 2025
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    Location:
    Southern California- Rancho Santa Margarita
    Vehicle:
    2002 Prius
    Model:
    Base
    Hello everyone! I have a 2002 1st Gen as my commuter car. It has 198k miles and its just now starting to have issues. 2 months ago it kicked out some misfire codes. Since then I changed the spark plugs, coils and fuel injectors. The codes went away and it ran perfectly until about a week ago. The misfire codes came back P0301 and P0304. I changed the spark plugs and coils around and still the codes came back. Now it has a "knocking" noise after a few seconds of turning on and struggles to accelerate. There is some smell of gas in the oil.
    Has anyone encountered this issue or have an idea of what it could be?
    My guess is the fuel pump... for the life of me, I cant find part number, however, i found one on ebay and ordered it not knowing if it is the right part number.

    Any help on getting a diagnose from anyone is much appreciated.
     
  2. ammdb

    ammdb Active Member

    Joined:
    Aug 8, 2019
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    Location:
    Indianapolis
    Vehicle:
    Other Electric Vehicle
    Model:
    N/A
  3. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    It might be hard to find a separate fuel pump part number for a gen 1. I am not sure it is replaceable except as a tank assembly.