1. Offline

    kaze72 New Member

    Member Since:
    Jul 3, 2007
    Posts:
    19
    Likes Received:
    4
    Hi,

    I've been driving an 2007 Prius unitl last week, when I upgraded to an 2010 model. I'm very happy with it so far.

    My question is however, when to use the Eco mode? I think it is pretty efficient in Normal mode. When does the Eco mode give me additional fuel savings? Is it design for any specific driving conditions?
  2. Offline

    stream Senior Member

    Member Since:
    May 12, 2008
    Posts:
    2,977
    Likes Received:
    443
    Location:
    Long Island, NY
    Your Vehicle Year:
    2010 Prius
    Model:
    V
    I never use ECO mode anymore. When I first got my Prius (my first hybrid), I decided to drive in ECO mode as default. Then a few members here posted how they were getting better MPG in "normal" mode than ECO, so I turned ECO off, and guess what--my MPG increase modestly ( a few MPG). No more ECO for me.

    There's info on the differences in the various modes in the owners manual (basically throttle sensitivity mapping and A/C settings, as I recall), and a bunch of threads here--a search will get you lots of info if you're interested.
  3. Offline

    Corwyn Energy Curmudgeon

    Member Since:
    Mar 6, 2011
    Posts:
    2,082
    Likes Received:
    608
    Location:
    Maine
    Your Vehicle Year:
    2007 Prius
    Model:
    II
    The car is no more or less efficient in Eco mode (except for running the AC a bit lower). The driver may be more efficient in Eco mode. By adjusting the response of the car to gas pedal, it makes it easier for the driver to perform some hypermiling techniques (like gliding and accelerating in the proper range). Eco mode makes the gas pedal more sensitive at small depressions, (and, of course, correspondingly less sensitive at large depressions). Power mode is the opposite. Normal is in between. Full power is available in all modes, should it be needed.
  4. Offline

    john1701a Prius Guru

    Member Since:
    Jan 6, 2004
    Posts:
    7,635
    Likes Received:
    1,832
    Location:
    Minnesota
    Your Vehicle Year:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    Watch what ECO mode does in the winter.

    ECO lowers the coolant threshold from 145°F down to 114°F.

    The result is the engine staying off longer, resulting in higher MPG.
  5. Offline

    kaze72 New Member

    Member Since:
    Jul 3, 2007
    Posts:
    19
    Likes Received:
    4
    Thanks for all your interesting answers. I think I will use Eco mode when driving in slow and very dense traffic.
  6. Offline

    Corwyn Energy Curmudgeon

    Member Since:
    Mar 6, 2011
    Posts:
    2,082
    Likes Received:
    608
    Location:
    Maine
    Your Vehicle Year:
    2007 Prius
    Model:
    II
    In order to truly get an idea about which mode one gets better MPG in, one should do an A-B-A test. That is, use one mode, switch, and then switch back, compare all three results. Otherwise, one can miss an unrelated change (like weather, or one's improving driving skills)
    sfv41901 and F8L like this.
  7. Offline

    szgabor Active Member

    Member Since:
    Jul 29, 2009
    Posts:
    757
    Likes Received:
    113
    Location:
    Oceanside NY
    Your Vehicle Year:
    2012 Prius
    Model:
    Two
    Never heard this before ... do you have some reference for this ???

    I do not like ECO mode I am less efficient with it and is harder in city driving ... but will start in ECO if this can be confirmed ... my commute starts out in local street with lights and stop signs so it would make a difference !!!
  8. Offline

    john1701a Prius Guru

    Member Since:
    Jan 6, 2004
    Posts:
    7,635
    Likes Received:
    1,832
    Location:
    Minnesota
    Your Vehicle Year:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    My blogs are loaded with real-world observations. We got pretty excited with the upgrade from Iconic to +2010, knowing the new ECO feature targeted thermal thresholds in addition to throttle play.
  9. Offline

    GasperG Member

    Member Since:
    May 13, 2011
    Posts:
    347
    Likes Received:
    68
    Location:
    Slovenia
    Your Vehicle Year:
    2010 Prius
    Model:
    N/A
    But in winter you would normally use heater, and the engine will run until cabin temperature is meet or coolant temperature is high enough to provide that heat. In winter (when no defrost is needed) I start to drive with ventilation off, and when ICE reaches its temperature then I turn it on, but even then in slow traffic ICE comes on just to provide cabin heat.

    So does this threshold for coolant temperature include heater on?
  10. Offline

    walter Lee Hypermiling Padawan

    Member Since:
    Oct 26, 2009
    Posts:
    968
    Likes Received:
    298
    Location:
    Maryland
    Your Vehicle Year:
    2010 Prius
    Model:
    III

    Why would ECO mode do this in the winter time but not the summer time? o_O
  11. Offline

    john1701a Prius Guru

    Member Since:
    Jan 6, 2004
    Posts:
    7,635
    Likes Received:
    1,832
    Location:
    Minnesota
    Your Vehicle Year:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    Yup. It extends the engine-off time, which is great considering how much slower winter traffic can be.


    It does then too. Coolant temperature isn't the only criteria though. The other is how fast the vehicle is moving. Watch the "green" zone on the Eco-Meter; exceeding that into the "white" starts the engine.
  12. Offline

    rpg51 Member

    Member Since:
    May 4, 2008
    Posts:
    200
    Likes Received:
    11
    Location:
    Vermont
    Your Vehicle Year:
    2012 Prius
    Model:
    Four
    This is where I draw the line. I like to be warm in the cold northern winters.
  13. Offline

    retired4999 Prius driver since 2005

    Member Since:
    Aug 11, 2011
    Posts:
    2,110
    Likes Received:
    460
    Location:
    Eau Claire, Wi.
    Your Vehicle Year:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    +1 Mine stays in ECO always, Thanks John! It will stay warm in eco mode no problem.
    Last edited by retired4999, Aug 20, 2012
  14. Offline

    rpg51 Member

    Member Since:
    May 4, 2008
    Posts:
    200
    Likes Received:
    11
    Location:
    Vermont
    Your Vehicle Year:
    2012 Prius
    Model:
    Four
    Could someone explain this a little more? I don't understand what is meant by thermal thresholds. Also, in cold winter climate, what impact does it have on cabin temperature. My big concern is keeping the windshield and windows warm enough to avoid fogging.
  15. Offline

    F8L Protecting Habitat & AG Lands

    Member Since:
    Aug 14, 2006
    Posts:
    18,629
    Likes Received:
    3,695
    Location:
    Sacramento, CA.
    Your Vehicle Year:
    2013 Chevy Volt
    Model:
    N/A
  16. Online

    Mendel Leisk Senior Member

    Member Since:
    Oct 17, 2010
    Posts:
    3,721
    Likes Received:
    620
    Location:
    Greater Vancouver, BC, Canada
    Your Vehicle Year:
    2010 Prius
    Model:
    N/A
    The main thing I disliked about ECO was the gas pedal travel: too much for my taste. I got tired of having to push further, further, to get a reaction. It's unfortunate, because there likely are other benefits, but that was the deal breaker.

    I just leave it in normal, I think it makes little or no difference to the bottom line mpg.

Share This Page