Very sluggish 2010 - help!

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Olive29, Feb 7, 2021.

  1. Olive29

    Olive29 New Member

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    I have a 2010 with 280k, and acceleration in eco mode is very sluggish when floored. The car is about 6 months new to me, so I don't have much to compare it to, but this is a new issue. It used to accelerate more quickly.
    It's dangerously slow...I haven't timed my 0-60 time in eco mode with the pedal floored, but i would guess it's in the range of minutes rather than seconds. In other words, if I'm getting all of the available power when floored, there's not much available.

    If i switch to power mode, acceleration is better, closer to but likely not quite the advertised 10-11 seconds - probably more in the 15 second realm.

    Any thoughts on how to diagnose?
     
  2. bisco

    bisco cookie crumbler

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    the car should perform the same in all 3 modes if you actually floor it. can you try a performance test with a stopwatch?
    at that mileage, i wouldn't expect the same as new. you might need a new battery, or it could be a myriad of engine problems.
    does she burn any oil?
    do you have the service history?
     
  3. rjparker

    rjparker Senior Member

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    Is the hv battery bar graph showing low? If your hv battery is discharged you are running on gas engine only.
     
  4. Olive29

    Olive29 New Member

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    Batteries looked good. Car is definitely not performing the same in all modes but is slower that it should be in all modes when floored (or otherwise). I'm guessing it's one of the myriad engine issues you mention. It's not burning a tangible amount of oil. I did just have the EGR cleaned thoroughly...it was really gunked up. i wonder if it didn't actually get completely cleaned...or whether there's another build-up of gunk elsewhere? Is there a 'start here - end there' check list I should go through to find the issue(s)?
     
  5. bisco

    bisco cookie crumbler

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    if it started after the egr cleaning, it may be related. take a look at @NutzAboutBolts youtube videos. perhaps they didn't do the whole circuit, or didn't reattach everything properly.

    after that, i would go through the maintenance schedule for your mileage. could be plugs, injectors, o2 sensors, dirty throttle body, air filter, etc.
     
  6. Mendel Leisk

    Mendel Leisk Sand Pounder

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    The complete Exhaust Gas Recirculation system needs cleaning. Starting at the exhaust connection and working forward, that’s the Exhaust Gas Recirculation cooler, valve and pipe. That last item connects to the intake manifold. Note: I’m using colloquial names, might be partially at odds with Toyota terminology, but they’re descriptive and common sense, what everyone here is using.

    the EGR gas flows from the aforementioned pipe into a gallery that runs across the intake manifold, then up through four, small diameter capillary passages, one for each engine intake port. Accordingly the intake manifold should be removed and thoroughly cleaned as well, in particular those four capillary passages.

    More info:

    Bad Flywheel | PriusChat
     
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  7. Olive29

    Olive29 New Member

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    Thanks for the EGR and youtube advice. Looking forward to taking a crack a the EGR system myself.
     
  8. OptimusPriustus

    OptimusPriustus Junior Member

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    Old thread but still: if there’s lack of power when flooring the egr would not be first thing i would check. When engine is maxing out it is asking fresh air 100% (= egr closed). Of course intake manifold can be badly clogged but i guess egr get clogged first thus it unlikely to happen.

    If no CEL in dash then how are the brakes? Hot and smell? When was air filter changed last time?

    if problem solved would be nice to know what was the root cause:)
     
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