Possible bad transmission? Please help

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Mike355F1, Mar 25, 2015.

  1. Mike355F1

    Mike355F1 Junior Member

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    My wife's 2006 Prius is having some problems. The car has 187,000 miles on it. When the engine starts it makes a continuous whirling or humming sound. WHen I try to drive it has minimal power and can not be driven above 15-20 mph on my street. I bought an inexpensive Actron code reader and got the following codes. P0A92 P0300 P0303 P0304 P3191. Does it sound like a definite transmission problem and those other codes are caused by the transmission problem. Any advice you can give is greatly appreciated. Thanks
     
  2. bisco

    bisco cookie crumbler

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    have the codes read at toyota, or get a mini vci and windows laptop.
     
  3. fuzzy1

    fuzzy1 Senior Member

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    Is the gasoline engine even starting at all? Or is it just being spun by the electric MGs without firing?
     
  4. Mike355F1

    Mike355F1 Junior Member

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    The gasoline engine will start but will cut out and not provide power. Seems the only power is coming from the electric motor
     
  5. Mike355F1

    Mike355F1 Junior Member

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    Also, the battery is down to one purple bar now
     
  6. fuzzy1

    fuzzy1 Senior Member

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    I'm not even close to being an expert on those codes, but from what I found about them, it seems more likely to be a problem with the gas engine (or its fuel or ignition systems) than with the 'transmission' or transaxle.
     
  7. bisco

    bisco cookie crumbler

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    the battery is low from trying to start the engine, and ev driving. don't take it any lower, or you'll need the special charger to bring it back to life.
     
  8. kenoarto

    kenoarto Senior Member

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    How old is the belt?
     
  9. Mike355F1

    Mike355F1 Junior Member

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    The serpentine belt? It is original to the car
     
  10. JC91006

    JC91006 Senior Member

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    1. The belt should have been changed at 100k miles, it drives the water pump which cools the engine.

    Most likely this car is dying from the lack of proper maintenance. If what Fuzzy is saying about the codes being engine related, I would first look into the engine stuff.

    1. spark plugs
    2. clean throttle body
    3. check injectors
    4. make sure engine has oil
    5. make sure the coolant is full (not leaking out from notoriously bad water pump)
     
  11. Mike355F1

    Mike355F1 Junior Member

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    The car is maintaned regularly with normal intervaled sythetic oil changes, the coolant has been changed, so has the spark plugs. I will look through the records to see if the belt has been changed and see if I can figure out how to test the injectors. The engine runs fine when it starts. It is my understanding that the transmission being bad could cause the starting/running issues as it is controled by mg1 right?
     
  12. Mike355F1

    Mike355F1 Junior Member

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    Also I have cleaned the throttle body several times throughout the years
     
  13. kenoarto

    kenoarto Senior Member

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    1) Always check the battery first. A low battery causes all kinds of odd stuff and throws wild codes 2) change that old belt immediately
     
  14. nh7o

    nh7o Off grid since 1980

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    To the OP: Assuming that the codes you list are accurate (cheap readers can give false codes):
    P0A92 MG1 has a problem (need Techstream to delineate further)
    P0300 P0303 P0304 Misfire (random, and cylinder 3 and 4)
    P3191 Engine does not start (many reasons, like out of gas, or above MG1 problem)

    If you want to DIY this, start by getting the mini VCI referred to above, and getting the INF codes for the DTC's to narrow the cause further. MG1 failures are quite rare, but certainly not unheard of. I don't think the serpentine belt or cooling issues are the root cause here.
     
  15. JTucson

    JTucson New Member

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    I have a 2005 Prius that I just took to a shop due to engine noise and not really running well plus tons of lights lit up on the dash. Sounds like some kind of grinding or rubbing noise when the car is running. The shop I went to gave me a code of P0A92-606 and noted I was low on oil as well. Based on your post above could the MG1 be going bad and making noises?" The maintenance history is dodgy on this car and I don't know if its ever had a water pump service on engine or inverter. The car currently has 220,000 miles on the odo. Any thoughts on this would be appreciated.
     
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