1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Sluggish Acceleration

Discussion in 'Gen 3 Prius Technical Discussion' started by GoMetricToday, Jan 8, 2013.

  1. GoMetricToday

    GoMetricToday 42 is the answer to the ultimate question.

    Joined:
    Jan 10, 2011
    64
    6
    9
    Location:
    Erwin, TN
    Vehicle:
    2010 Prius
    Model:
    II
    I have a question and I am hoping someone could possibly help. Lately I have found that when I am trying to go up an incline on my road, that my car has trouble accelerating. Almost as if the engine is being choked off like it is about to stall or is out of gas. I have to press the accelerator almost to the floor to get up the incline. The suddenly it will lurch and accelerate rapidly as if I have put the car in Power Mode.
    I should also add that this only happens when the engine is cold. I didn't have this problem last year at all. I usually wait a couple of minutes after the engine starts before I try to drive, but that doesn't seem to help. Any suggestions anyone?
     
    #1 GoMetricToday, Jan 8, 2013
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    how many miles on her?
     
    #2 bisco, Jan 8, 2013
  3. spiderman

    spiderman wretched

    Joined:
    Jul 5, 2009
    7,543
    1,558
    0
    Location:
    Alaska
    Vehicle:
    2010 Prius
    Model:
    II
    Normal. During the warm-up stages, the mixture is rich and the results is sluggish excel. You can push through it by flooring the pedal, though not recommended.
     
    #3 spiderman, Jan 8, 2013
  4. Former Member 68813

    Former Member 68813 Senior Member

    Joined:
    Oct 3, 2010
    3,524
    981
    8
    Location:
    US
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Sounds normal on cold engine, not sure why you didn't have it last year. Is the coolant temp sensor working OK?
     
    #4 Former Member 68813, Jan 8, 2013
  5. GoMetricToday

    GoMetricToday 42 is the answer to the ultimate question.

    Joined:
    Jan 10, 2011
    64
    6
    9
    Location:
    Erwin, TN
    Vehicle:
    2010 Prius
    Model:
    II
    Less than 16K. I went to the dealership today and the technician said that I would need a software update. I found it strange since I haven't seen anything on here about the 2010 models needing a software update.
     
    #5 GoMetricToday, Jan 8, 2013
  6. GoMetricToday

    GoMetricToday 42 is the answer to the ultimate question.

    Joined:
    Jan 10, 2011
    64
    6
    9
    Location:
    Erwin, TN
    Vehicle:
    2010 Prius
    Model:
    II
    I went to the dealership today and the technician said that I would need a software update. I found it strange since I haven't seen anything on here about the 2010 models needing a software update.

    I have also had this funny thing happen. Shortly after starting the car. Whilst the engine is cold it would shut off shortly after starting (just the engine not the whole car). Then it would restart.
     
    #6 GoMetricToday, Jan 8, 2013
  7. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    let us know what happens after the software update. afik, software doesn't change on it's own, so i'm not sure why this would be a new problem. have you had the car since new?
     
    #7 bisco, Jan 8, 2013
  8. GoMetricToday

    GoMetricToday 42 is the answer to the ultimate question.

    Joined:
    Jan 10, 2011
    64
    6
    9
    Location:
    Erwin, TN
    Vehicle:
    2010 Prius
    Model:
    II
    Yes when I purchased the car it only had 7 miles on it.
     
    #8 GoMetricToday, Jan 8, 2013
  9. Sergio-PL

    Sergio-PL Member

    Joined:
    Jun 24, 2011
    160
    46
    0
    Location:
    Poland
    Vehicle:
    2011 Prius
    Model:
    N/A
    Isn't your incline within first 60 seconds from starting the car? If yes you are in first (S0) warm-up stage, where engine preheats and ECU does everything possible to use battery power only to move the car. If you have step incline and you go to PWR zone engine will rapidly spin up and climb that hill. This is some kind of emergency override in case you have to accelerate very quickly.

    I would suggest to wait 60 seconds from switching to READY mode (very audible change in engine noise) and then try to climb. If it will go normal you have the answer. Everything is fine.

    If it's not that case - try to isolate and debug all variables from equations. How long car has been switched off, how long (in time and in distance) is from starting car to reach the incline.

    When you first start cold car it will start combusion engine (ICE) about 10 seconds from switching to READY and will spin in in special, low power mode for 50 seconds. Then, depending on heat requirements and outside temperature it will turn off or keep working to heat up water and then car interior.
     
    #9 Sergio-PL, Jan 8, 2013
    GoMetricToday likes this.
  10. GoMetricToday

    GoMetricToday 42 is the answer to the ultimate question.

    Joined:
    Jan 10, 2011
    64
    6
    9
    Location:
    Erwin, TN
    Vehicle:
    2010 Prius
    Model:
    II
    Thank you. What you described is exactly what is going on. I will give it more time in the future before driving. My incline happens starting from my driveway and then about 100 yards after I leave my driveway. I will hold off on the software update for now. Thanks again.
     
    #10 GoMetricToday, Jan 8, 2013
  11. lhsu

    lhsu Junior Member

    Joined:
    Jul 26, 2012
    18
    2
    0
    Location:
    Malaysia
    Vehicle:
    2012 Prius
    Model:
    N/A
    I guess your " Sluggish Acceleration" is the same thing that happened to me.

    See here:
    Acceleration- no response | PriusChat

    So, yours problem was about heating and mine still remain unknown... :unsure:
     
    #11 lhsu, Jan 9, 2013
(You must log in or sign up to post here.)