engine working too hard - help?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by sanders, Jun 9, 2016.

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  1. sanders

    sanders Junior Member

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    I have a 2005 generation 2 Prius with 222,000 miles on it. Over about the last 400 miles it seems like the gasoline engine is working too hard. Instead of a nice quiet purr, it is louder and sounds choppy. It doesn't start smoothly, but lurches a little bit when it starts and stops. It sounds like it's spinning faster/louder than it used to when accelerating, and it runs longer when I stop at a stoplight. Any ideas?

    I changed the oil recently but that didn't help. On the most recent tank of gas I added Lucas Upper Cylinder Lubricant but I haven't noticed a difference, other than very slightly improved gas mileage, which I expected.

    Thanks!!
     
    #1 sanders, Jun 9, 2016
  2. JC91006

    JC91006 Senior Member

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    1. Clean your throttle body and MAF sensor
    2. Check and possibly change the air filter.
    3. How's the 12v battery health?
    4. Have you changed the spark plugs?
     
    #2 JC91006, Jun 9, 2016
  3. sorka

    sorka Active Member

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    My vote is either the main traction battery is going bad so your ICE has to work harder. What you describe sounds exactly what happens when the battery falls to two bars. But if the internal resistance has finally risen high enough to cause a significant voltage drop at the same current, the effect would be the same even with more than 2 bars.

    The other possibility is the MG1 is starting to fail resulting in the ICE not being able to direct torque at the main drive ring.

    Both of these can be confirmed with a CANBUS logger for the Prius.

    Does anyone know what the normal voltage drop on the main battery is when it's charge to 6 bars or so?

    BTW, I just hit 222K miles on mine as well. The only problem I've had was that I got P0420 for the cat but it hasn't come back in 500 miles since the acid cleaning I did last week.
     
    #3 sorka, Jun 9, 2016
  4. bisco

    bisco cookie crumbler

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    allow mileage replacement engine is not too expensive.
     
    #4 bisco, Jun 9, 2016
  5. sanders

    sanders Junior Member

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    Thank you for your suggestions.
    1/2. I will clean the throttle body and MAF sensor, and check the air filter.
    3. I haven't noticed any problems with the 12 volt battery. Is there something in particular that I should check to determine 12 volt battery health?
    4. I have not changed the spark plugs. I bought the car at 207,000 miles a year ago and don't know the maintenance history before that. How do I know when the spark plugs need to be changed?
    Thanks again.
     
    #5 sanders, Jun 10, 2016
  6. sanders

    sanders Junior Member

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    Perfect, thank you for your ideas. I'm afraid I don't know what a CANBUS logger is. Could you direct me?
     
    #6 sanders, Jun 10, 2016
  7. sorka

    sorka Active Member

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    #7 sorka, Jun 10, 2016
  8. Former Member 68813

    Former Member 68813 Senior Member

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    you will know when you remove them and look at them. possibly never replaced in those 222000 miles.
     
    #8 Former Member 68813, Jun 11, 2016
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    One way to know is when the engine is not performing normally, the spark plugs should be one of the first items to check. Use the correct NGK or Denso iridium spark plugs - do not install an inferior-quality plug. The correct plugs have a service life of 120K miles.
     
    #9 Patrick Wong, Jun 11, 2016
  10. wjtracy

    wjtracy Senior Member

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    We've had a few cases in Northeast where the exhaust manifold rusted through probably due to salt on the roads. Not the exhuast pipe..that is stainless steel, but the rusty steel piece that connects up to the engine...pics elsewhere on here
     
    #10 wjtracy, Jun 11, 2016
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