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Rough running

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by taxidriver50005, Mar 5, 2017.

  1. taxidriver50005

    taxidriver50005 Active Member

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    My 09 gen 3 prius showing 194000 miles has a slight rough spot on low throttle openings, my thinking is maybe a clogged injector. My thoughts on this are the car runs perfectly when cold on choke but as soon as the warmup cycle has finished (using Android assistant to see when engine is in s4 mode) the rough running begins. Feels like a slight misfire but seems better on higher throttle openings. Have changed the spark plugs and I'm going to swap out coil packs tomorrow with a good set on my other prius. EGR moves freely is there anything else I could check before sending injectors off to be cleaned and checked.

    Posted via the PriusChat mobile app.
     
    #1 taxidriver50005, Mar 5, 2017
  2. m.wynn

    m.wynn Senior Member

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    No check engine light - P0401, P030x?... Engine coolant level stable in the reservoir?

    You are likely on the right track suspecting EGR even if no code and the valve seems fine. Pull the EGR pipe and the intake manifold and inspect EGR passages the entire length of the manifold. Good chance they are sludged to nearly complete blockage. At your mileage, the EGR valve cooler may be clogged too, but if no P0401 I would start by inspecting the intake side of the circuit. Toyota did less than perfect design work with the Gen 3, cooled EGR. Scores of threads here on PriusChat.
     

    Attached Files:

    #2 m.wynn, Mar 5, 2017
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  3. taxidriver50005

    taxidriver50005 Active Member

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    No check lights at all and EGR has been replaced about 70,000miles ago. Had a quick look at EGR pipe and that was very clean. How bad do these intake manifolds get.

    Posted via the PriusChat mobile app.
     
    #3 taxidriver50005, Mar 5, 2017
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  4. Raytheeagle

    Raytheeagle Senior Member

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    They can get pretty clogged:(.

    When was the last time you looked at the egr pipe: 70 k miles ago when the valve was replaced, or recently? How fast do you rack the miles up on an annual basis? Has the PCV valve been changed? Do you consume any oil between oil changes? What oil do you use?

    Keep us posted(y)!
     
    #4 Raytheeagle, Mar 5, 2017
  5. taxidriver50005

    taxidriver50005 Active Member

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    EGR pipe looked at last week, wifes car doing about 10k a year now. Pcv and plugs changed this week and runing on 0w20 Toyota oil. The guy I bought this from recently just threw it in dealership whenever a problem acured. The rough spot isn't bad and if I didnt already have another prius, low mileage I don't think I would have even noticed it and just put it down to character or the car. From what I've seen of these inlet manifolds they don't seem bad to me but I do come from a 30yr history of diesel cars and they can get pretty bad without affecting anything. Think tomorrows jobs are swop out coil packs from one car to other, Clean MAF sensor as I've read these can affect things although I'm not sure how it would affect drivability, I know on diesels it usually puts you in limp home mode with no turbo boost. Have people had issues with injectors on these cars, my main reason for thinking Injectors was the car runs fine until its warmed up properly and I was thinking it could be a lean misfire if it's getting a bad spray pattern or slightly clogged.

    Posted via the PriusChat mobile app.
     
    #5 taxidriver50005, Mar 5, 2017
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  6. Raytheeagle

    Raytheeagle Senior Member

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    The MAF sensor is easy to knock off the list.

    What about oil consumption between changes: is there any?

    The egr inlets in the intake manifold are in the bottom side, which with the oil blow by of the Atkinson style engine, leads to a gummy mess. Worth a look to see as the reduction in air flow returning from the egr system can cause poor performance. If doing the intake manifold removal, it is also worth cleaning the throttle body.

    Do you use any fuel injector cleaner? Might be worth doing on occasion.

    Keep us posted (y).
     
    #6 Raytheeagle, Mar 5, 2017
  7. taxidriver50005

    taxidriver50005 Active Member

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    Not had car long enough to do an oil change yet and burnt any oil either, but my wife drives sedately and not to often on motorway, as for injector cleaner already put some in but would love to see some real concrete results on how well these work.

    Posted via the PriusChat mobile app.
     
    #7 taxidriver50005, Mar 5, 2017
  8. taxidriver50005

    taxidriver50005 Active Member

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    Oh did check bottom of manifold when checking EGR pipe and that looked pretty good too.

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    #8 taxidriver50005, Mar 5, 2017
  9. Raytheeagle

    Raytheeagle Senior Member

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    Here's a post I made in an oil consumption thread that describes some information around fuel injection and oil additives as well:

    [POLL] Excessive Oil Usage

    While it isn't "concrete" and the opinion of a preventative maintenance company, it doesn't deter me from using their products or experimenting.

    Concrete data is hard to find and there are many factors that all can contribute different ways toward the end performance of an engine.

    Hope this helps (y).
     
    #9 Raytheeagle, Mar 5, 2017
  10. taxidriver50005

    taxidriver50005 Active Member

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    Oh well tryed cleaning MAF and changing coil packs, no difference now to clean inlet manifold

    Posted via the PriusChat mobile app.
     
    #10 taxidriver50005, Mar 6, 2017
  11. taxidriver50005

    taxidriver50005 Active Member

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    ok now cleaned inlet manifold and found a blockage in one of the egr pipes feeding the cylinder, down side is now got the check hybrid system light on. what could I have done and what to check next
     
    #11 taxidriver50005, Mar 6, 2017
  12. taxidriver50005

    taxidriver50005 Active Member

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    #12 taxidriver50005, Mar 6, 2017
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  13. m.wynn

    m.wynn Senior Member

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    You left the PCV hose disconnected or the MAP (not MAF) sensor harness unplugged is the likely scenario. This will cause check hybrid message and P0A0F. Ask me how I know? Anyway, if you don't want to pull the manifold again, you can access from under the car but you'll need to pull the plastic under tray. I'm not sure which approach is worse...

    Assuming you cleaned all EGR ports the entire length of the manifold, it's time to test drive. Is engine coolant level stable?
     
    #13 m.wynn, Mar 6, 2017
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  14. taxidriver50005

    taxidriver50005 Active Member

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    Erm..... Erm.... Erm...... Yup left hose off..... What a prat.... Right been out for test drive and............ Big pause for suspense........ Sorted thank you everybody for your help.... Surprisingly easy job to do if you remember to put it back together properly.

    Posted via the PriusChat mobile app.
     
    #14 taxidriver50005, Mar 6, 2017
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