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35 MPs and no acceleration in my 2010 Prius :(

Discussion in 'Gen 3 Prius Main Forum' started by Al Martin, Jun 16, 2019.

  1. Al Martin

    Al Martin New Member

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    Location:
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    Vehicle:
    2010 Prius
    Model:
    Five
    I’ve spoken to a couple different bonehead mechanics and nobody can explain my 35 miles per gallon overall, back of my car getting dirty from exhaust, no acceleration and burning over a quart of oil every thousand miles or so. Not sure if any of these symptoms are related but I signed up for this chat group hoping for some input Before going to Toyota mechanics and spending money I don’t have, PS I am a poor broke Uber driver with over 160k miles on my Prius...I don’t know if that solicitation for help will work but worth putting it out there thank you smart people that help me
     
  2. jerrymildred

    jerrymildred Senior Member

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    Soot. No power. Bonehead mechanics is right. The 2010 has earned quite a reputation as an oil burner.

    Any decent mechanic should be able to check the compression and tell you the best course of action. Toyota SHOULD give you dependable answers but they can be mighty expensive. Sure seems odd the engine would be that shot after only 160k miles unless someone ran it out of oil. That'll trash an engine in no time flat.
     
  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    At first blush it sounds like two unrelated problems: oil burning is a "feature" of 2010s, and the hybrid power system isn't performing up to scratch.

    Oil burning is entirely within the engine, and it's not much different from any other gasoline engine with an oil burning problem. Same kinds of fixes and expenses. Not pretty.

    Hybrid trouble is different- If the battery or inverter is getting too hot, the computer will automatically reduce power available. This causes the gas engine to do more of the work, resulting in low MPG and poor acceleration. Check battery cooling fan, clean vents & ducts with a vacuum. Check inverter coolant level and radiator fan performance.

    Now, if the hybrid battery is shot, you can get similar symptoms. Hopefully it isn't that.

    You can get instruments and phone apps that let you monitor this stuff as you drive. Some of them are very inexpensive.
     
  4. bisco

    bisco cookie crumbler

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    welcome!
    have you cleaned the egr circuit?
     
    Raytheeagle likes this.
  5. Raytheeagle

    Raytheeagle Senior Member

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    How often do you check the oil level?
    How long have you owned your Prius?
    What type of driving do you do as an Uber driver in San Diego: mostly city, mostly highway?
    Tire pressure you maintain?

    There are a lot of variables that cause the mpgs to be low.

    Good luck and keep us posted (y).
     
  6. jerrymildred

    jerrymildred Senior Member

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    Yeah, but soot on the back of the car. Never should happen with a Prius.
     
  7. Raytheeagle

    Raytheeagle Senior Member

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    I’ve seen plenty of Corollas and Camrys out here with the same condition:cool:.

    Not saying it’s right, or that it’s unique ;).

    Just that when you have a car and pile on the mileage, there are things you need to monitor as things will not always stay the same:whistle:.

    If oil burn is the worst problem to have later on in a vehicles life, sign me up as I check the oil level in both the Prime and RX450H every Saturday :).

    You stay ahead of it through data and responding to the data as each situation is different(y).
     
  8. bobzchemist

    bobzchemist Active Member

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    Vehicle:
    2010 Prius
    Model:
    IV
    There's a page here somewhere with diagnostic steps to take/report to us. Probably the very first thing I'd try (after making sure you have oil in the car and your tires are properly inflated) is to see what your mpg is on a highway at a constant speed, say 65 mph on cruise control for at least 30 minutes. This will give you a baseline mpg that you can check improvements against.

    The Prius is sensitive to some things conventional cars aren't - the 12v battery, for example. And the mpg of a cold engine isn't good at all.

    On top of engine/battery issues, there's a whole host of mechanical things that can reduce mpg - improper alignment, tire pressure low, brakes sticking, wheel bearings going bad, etc.

    There's a lot to check.
     
  9. bobzchemist

    bobzchemist Active Member

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    The lack of acceleration is concerning - is it the same in eco, normal, and power mode?
     
  10. The Critic

    The Critic Resident Critic

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    Lack of acceleration is a bit subjective. Did you recently purchase this car? Or is this a change that you have observed?

    How much oil are you drinking?

    If you are burning enough oil to clog the catalytic converter you can check the exhaust backpressure.