P0302 and fuel injectors

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by ZoidbergMD, Aug 3, 2019.

  1. ZoidbergMD

    ZoidbergMD New Member

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    2010 Prius.

    I have been getting P0302 code a lot lately - probably 5 or 6 in the last 2 months. I replaced my coils and my spark plugs. Put in fuel system cleaner. From what I've researched, I want to attempt to go after the fuel injectors next - replace them.

    On RockAuto I have bought (but still have time to return) 4 of these - guess since i just registered today i can't post the link but this is what I got GB REMANUFACTURING 84212373

    Before I do this - am I down the right path? Any detailed procedures on how to replace them? Or how to depressurized the fuel system?

    I've used the search function and didn't find anything.
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Get the factory repair manual at techinfo.toyota.com

    To depressurize the fuel system, find the wiring harness to the fuel pump under the rear seat cushion. Make the Prius READY and put it in inspection mode so the engine will continuously run. Disconnect the fuel pump and wait for the engine to stall.

    There are a lot of steps to get to the fuel injectors, so follow the repair manual instructions. It is necessary to remove the EGR with cooler pipe subassembly, disconnect the fuel line from the fuel delivery pipe, pull the fuel delivery pipe and four injectors away from the engine, then remove the individual injectors.

    You should install new injector O-rings and they should be lubricated with gasoline or a thin oil (the manual refers to spindle oil) to avoid damaging or twisting the rubber.

    If you haven't tried cleaning the EGR system yet, I would suggest you do that first.
     
  3. tankyuong

    tankyuong Senior Member

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    Egr circuit,injectors are hardly the cause
     
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  4. ChapmanF

    ChapmanF Senior Member

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    Misfires are sometimes caused by injectors and sometimes not. There are ways of finding out, but I never heard that internet clairvoyance from 530 miles away was one of them.
     
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  5. afpri

    afpri Hemi-Hybrid

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    I'm having this exact issue. I have already done the EGR pipe, cooler and Valve. the valve moves freely and these are all clean. I also changed the spark plugs with iridium. swapped the ignition coils and cleaned the intake manifold and reinstalled. So, i'm assuming that fuel delivery is the only thing left. anyone have any suggestions? injectors or filter? is there an inline filter between the pump and the fuel rails? thank you
     
  6. Mendel Leisk

    Mendel Leisk 'Orrible Oracle

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    I think no.

    If you're getting this code, done all that work and code's still there, my guess would be head gasket failure. Try a leak-down test?

    How many miles on it btw, and how recently did you do the cleaning?
     
  7. afpri

    afpri Hemi-Hybrid

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    thank you so much for the reply @Mendel Leisk (and for posting this in the right thread)

    I did the work a few hundred miles ago. I wanted to add a few symptoms which may point to the head gasket, unfortunately.

    1. this was a traumatic occurence after driving 6 consecutive hours I was on the last bar of fuel so i stopped and refilled the tank at a station I am unfamiliar with. it was 20 degrees. shortly after the fill up the knocking started. I was told extremely cold fuel into a hot motor could induce a looming head gasket failure by an autozone employee that seemed pretty knowledgeable.

    2. After i did the EGR stuff and the plugs the misfiring got significantly less. in fact, it only happens on a warm engine, so for the first 10-20 minutes of driving it doesn't happen at all.

    3. i finally decided to try cleaning the Intake manifold and PCV valve even though I doubted these as culprits. the PCV had sludge occluding 15% of the opening and I got it all out and replaced it. the intake manifold was coked up pretty good. I cleaned it pursuant to Nutzaboutbolts video on Youtube but I am a novice car mechanic at best. The car doesn't want to heat up now. cabin air is cold for the duration of most of my drives. is it possible I hooked up the coolant lines to the intake backwards? this is not extremely likely, but i suppose i could have jacked it up. the guy at autozone told me if the head gasket is the problem then the water pump would not be getting enough pressure to overcome the engine lacking pressure. or some such comment. it's over my head a little bit.

    4. So, also, this morning the coolant line that comes from the reservoir on the passenger side, which goes into a plastic Y device over top of the radiator blew open and spewed coolant all over the intake and caused a ludicrous amount of smoke in the engine bay and cabin. I had to pull over and clear it all out. when i finally realized it was just a plastic part that I probably hit with a tool and weakened it to the point of breaking under stress. anyway, i ask this after the coolant line question because I wanted you to have all the gory details. this problem is really kicking my nice person. UGHH.

    thank you for any help you or anyone can provide!!
     
  8. Mendel Leisk

    Mendel Leisk 'Orrible Oracle

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    A leak-down test should reveal if the head gasket is failing, and how it's leaking, ie: what's leaking into what. I think that coolant hose coming off could be related, but not sure how.
     
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  9. ChapmanF

    ChapmanF Senior Member

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    Combustion pressure leaking into the coolant passages would tend to increase the pressure inside the cooling system....
     
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