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2008 Prius losing power - Need troubleshooting help.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by SWprius08, Nov 25, 2014.

  1. SWprius08

    SWprius08 SoCalprius

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    Hello Guys, I had started another post regarding this and thought the problem got fixed but it did not, let me start all over again and will list all measures taken. Please help me find the issue to get it fixed.

    Vehicle: 2008 Prius Base, 90,000 miles.
    Problem: Lost Power from engine (read more details below in description)
    Observations: No check engine, no codes, dealer has no recommendation / unable to find the issue.
    Measures taken: Changed transaxle fluid, throttle body cleaned, spark plugs changed.
    What seems to help: As far as tank had a fuel injector cleaner the car runs a little better (not completely normal tho), with next tank of gas with no additives the power seems to get lost.

    Description: From stop when I push the gas pedal for gaining quick speed the engine turns on but does not deliver enough power corresponding to the depression of the pedal, after few seconds the engine revs up suddenly and provides power. This sudden revving of engine never happened before. This is more evident when the HV battery is low and the car is relying mostly on the power of the engine. I asked the dealer to look at it when I brought in for service, said he was not able to find the issue. I compared the sound of the engine with another gen2 prius with 60,000 miles and mine does seem to be a bit more louder. I put it in inspection mode and felt descent vibration on the engine area not sure if this vibration is normal, how can I find if the vibration is normal? Makes me think the valve clearance might be out due to this vibration and the louder noise of the engine, but the dealer did not find issues, I know for sure this is not how my car was when new, does anyone else relate to this issue? Any fixes? I see other gen 2 prius's making a quicker pickup then mine, other frustrated drivers behind me would change their lanes, I don't want to push as I feel as the sound of engine keeps getting louder but with not much power provided.

    Only work done around the engine were

    1) Changed the inverter pump by dealer during recall at about 30,000 miles
    2) changed the Engine pump, coolant and belt from non-dealer, at about 60,000 miles as hard pink oil had built up around the pump.

    I have noticed this issue since around 65,000 miles, but it has been at the dealer for regular oil change and service atleast 5 times since then, if the non-dealer would have done anything incorrectly the dealer would have caught it (I would think)
     
    #1 SWprius08, Nov 25, 2014
    Last edited by a moderator: Nov 26, 2014
  2. nh7o

    nh7o Off grid since 1980

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    Dealers may not be much use of if there are no DTC. Perhaps an independent, like Avi's Advanced Automotive is appropriate.
     
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  3. SWprius08

    SWprius08 SoCalprius

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    thanks i will get in touch with them, they are not far from me
     
  4. bisco

    bisco cookie crumbler

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    is the belt tensioned correctly?
     
  5. SWprius08

    SWprius08 SoCalprius

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    the belt was first replaced at the dealers place then few months later i purchased an oem pump new online and had a local repair shop replace it, i dont know whether he had to play with the tension of the belt or not to replace the pump. Answer is I dont know, but how can I check it?
     
  6. bisco

    bisco cookie crumbler

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    you need a belt tensioner. you can have avi check it.
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. To check the serpentine belt tension, apply 22 lb. force at the center of the longest run of the belt, between the crankshaft pulley and the idler pulley. The belt should deflect 0.4". I doubt this issue is related to your car's lack of performance.
    2. What does the engine air filter look like? Remove the filter and look at the bottom. Hold the filter up to the sun and if you cannot see light coming through, replace the filter.
    3. Check the pressure in each tire. Make sure that all four tires are the same size.
    4. Was the dealer tech able to replicate the driveability concern that you had reported?
    5. If you don't find any issues with 1-3 above, I suggest that you try disconnecting the 12V battery negative cable for a minute or so, then reconnect. It is pretty easy to disconnect the cable where it bolts to the body. While you are in there, make sure that both the positive and negative cable connectors at the battery are tight. The purpose of removing power is to allow the various ECUs to power down and then reboot when the power is reconnected. Maybe that will help - it will not hurt.
     
    #7 Patrick Wong, Nov 25, 2014
    Last edited: Nov 25, 2014
  8. SWprius08

    SWprius08 SoCalprius

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    patrick

    I will check the air filter.

    yes all 4 tires are new and i have noticed this issue even with old tires.

    200 miles ago the 12v battery was replaced as it was dying so i doubt #5 will help.

    dealer just told me that they were not ableto duplicate the problem.
     
  9. bisco

    bisco cookie crumbler

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    check your oil level, and ask the service manager to go for a ride with you, is it intermitent?
     
  10. SWprius08

    SWprius08 SoCalprius

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    no the problem is not intermittent, just had the 90k service done so oil levels should be ok.
     
  11. JC91006

    JC91006 Senior Member

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    If you notice improvement with a fuel addictive, try it with higher octane fuel.

    I don't think valve clearance is an issue, mine needs adjustment and the car feels more powerful than any other one that doesn't require adjustment.

    You can also try adding some marvel mystery oil to your fuel. About 4oz per tank. Drive it really hard for about 4 tanks and you should be able to see improvement
     
  12. SWprius08

    SWprius08 SoCalprius

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    well I would say when the car is cold (mornings or not driven for long time) the revving up is worst compared to the times when the engine is warm and has already been running

    The dealer's service adviser said that after 5000 miles I should look into fuel lines cleaning job for about $ 150. Since the additive is helping should I get that done now maybe, do you think that will help?
     
    #12 SWprius08, Nov 25, 2014
    Last edited by a moderator: Nov 26, 2014
  13. JC91006

    JC91006 Senior Member

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    Clean it with 4 tanks of gas and marvel mystery oil. 4oz per tank. It's about $5 for 32oz at walmart
     
  14. SWprius08

    SWprius08 SoCalprius

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    Would you mind sharing the symptoms of your prius that has necessitated adjusting the valve clearance.

    I have about 4 dots of gas left that has Techron fuel system cleaner, once that is completed I would love to try the Marvel Mystery, have never used it, hopefully using this solves the issue.
     
    #14 SWprius08, Nov 26, 2014
    Last edited by a moderator: Nov 26, 2014
  15. Patrick Wong

    Patrick Wong DIY Enthusiast

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    If the problem is not intermittent, then you should be able to demonstrate the problem upon demand.

    If you can demonstrate the problem then you should be able to take your dealer's service writer or mechanic on a test drive to show him/her what the problem is. If the mechanic can experience the problem, maybe something will be done about the issue.
     
    #15 Patrick Wong, Nov 26, 2014
    Last edited: Nov 26, 2014
  16. SWprius08

    SWprius08 SoCalprius

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    Yes I failed to do that last time, I thought the problem was so obvious that they will figure it out themselves, however they did not. Here is my plan of action

    1) Check Engine Air filter and report, replace if necessary
    2) After current tank is finished fill it up and add 4 oz of Marvel Mystery for 4 tanks

    if above 2 do not solve the issue then take it to the dealer for the below

    1) Have them check the pulley tension
    2) Ask the service advisor to go with me for a test drive and demonstrate the problem, would even offer him to drive while I am in the passenger seat.

    if the dealer fails then take it to Avi's advanced automotive.
     
  17. JC91006

    JC91006 Senior Member

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    The pulley tension would not affect the power in the car. That pulley only operates the ICE coolant pump, nothing more. I would not be surprised if the problem is related to your ignition coils or your injectors. Both have been reported as problem areas on the Prius cars.
     
  18. bisco

    bisco cookie crumbler

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    you may have to leave the vehicle overnight, then meet them in the morning for the test drive so it will be coldi would still check the oil level, dealers have made mistakes on occasionyou may have to dig into the throttle body again. sometimes people spray too much cleaner in there.
     
  19. Easy Rider 2

    Easy Rider 2 Senior Member

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    In a situation like this you should NOT assume anything.

    Including assuming that the new battery is really good.
    I normally would assume that an actual shop would check the charging voltage when they do a new battery........but that sometimes is a mistake too.

    I think you need a good check of the 12 V system and if it proves good then I agree with the "ride along and I will SHOW you the problem" suggestion.

    MMO is NOT advertised or intended to be a "cleaner". It is a light oil, good for upper cylinder lube and other "penetrating oil" type uses.

    If dirty injectors are suspect here, get some Berrymans B12 Chemtool and put in a double dose (2 OZ per gallon of gas instead of 1).
    If that makes a marked difference but the problem comes back, then you have a fuel pressure problem (restricted fuel flow) or you have one or more injectors that need to be manually cleaned or replaced.
     
  20. SWprius08

    SWprius08 SoCalprius

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    Hello Easy Rider, I actually have used Berrymans B12 Chemtool based on your suggestion from another post, I used it back to back in 2 tanks double dose, however as far as I had tanks of gas with this additive the car ran better (but not normal), however next tank with no B12 and the performance went back to where it was.