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

new drive belt/loss of mileage

Discussion in 'Gen 2 Prius Technical Discussion' started by swanbeach, Dec 18, 2011.

  1. swanbeach

    swanbeach Junior Member

    Joined:
    Sep 30, 2008
    3
    2
    0
    Location:
    Banner Elk, NC
    Vehicle:
    2007 Prius
    My 2007 Prius with 85000 mi just went in to dealer for service due to engine warning light. Warning light was due to coolant flow valve need replacement. Okay. done, while there also let them replace drive belt and do front end alignment. Had to take back because light came back on. Air lock in coolant, not bled properly. They took care of it. But... the car now feels like it is stuck in tar. Either high rolling resistance, or engine loading. Going downhill, I lose speed rather than having to use engine braking like normal on that hill. Mileage has dropped by about 15% on same daily round trip.
    Do not notice any unusual wear on tires from the alignment (yet). What might be the cause of this??
     
    #1 swanbeach, Dec 18, 2011
  2. tanglefoot

    tanglefoot Whee!

    Joined:
    Mar 27, 2007
    625
    188
    0
    Location:
    Colorado
    Vehicle:
    2007 Prius
    Did the dealer lower the tire pressure?
     
    #2 tanglefoot, Dec 18, 2011
    1 person likes this.
  3. Rokeby

    Rokeby Member

    Joined:
    Jan 21, 2008
    3,033
    708
    75
    Location:
    Ballamer, Merlin
    Vehicle:
    2008 Prius
    +1 on checking the tire pressure.

    For the record, did you get a report of before and after readings on
    the alignment?

    I don't want to get you bummed out at your dealership if you aren't
    already. But...

    There is the possibility that they set the tension in the serpentine belt
    too tightly. You would most likely notice this by the smell of hot or
    burning rubbber or a hot belt after the engine has run for a while.
    Further, the overly tight belt could lead to early failure of the belt
    tensioner bearing failing.

    Typically, 1/3 to 1/2 in. slack is recommended in the longest run in
    the belt.

    Here are two links for more info:

    Yahoo! Groups

    http://priuschat.com/forums/knowledge-base-articles-discussion/87166-belt-change-how-photos.html

    I'm hoping that I'm way wrong on this.
     
    #3 Rokeby, Dec 18, 2011
  4. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    10,096
    4,805
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Yes if they did a front end align they usually put tire pressure to the sticker on the door which is quite low like 28 lbs IIRC.
    Pump them back up to 44-42. Thats good for about 3 mpg's.
    God I hope your still not running Goodyear Integrities? :(

    Also your way overdue for Inverter coolant change and trans fluid change. Inverter coolant is pretty easy no special tools needed except a socket to open up the coolant dump in the trans.Trans a a bit trickier but both very easy for a shade tree mechanic.
    Both require putting the front end of the car up on a ramp.

    Oh and I assume your Inverter coolant pump has been replaced for the recall on the car?
     
    #4 edthefox5, Dec 18, 2011
(You must log in or sign up to post here.)