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

Mpg from 47 to 40

Discussion in 'Gen 2 Prius Fuel Economy' started by briand, Oct 12, 2009.

  1. briand

    briand Junior Member

    Joined:
    Aug 14, 2008
    15
    0
    5
    Location:
    Charlotte, nc
    Vehicle:
    2004 Prius
    This past weekend we took a trip from Charlotte to Atlanta. My Prius is a 2004 with 108,000 miles on it. I normally get 47 mpg but on this trip I averaged 39-40 mpg. Since its fall and the A/C is running I should have got slightly better than average mpg. My tires or tire psi haven't changed.
    What could cause this drop in average?
    I have looked through the schedule maintenance book and there is no major service until 150,000 mi which is spark plugs and coolant. So what gives?
     
    #1 briand, Oct 12, 2009
  2. usbseawolf2000

    usbseawolf2000 HSD PhD

    Joined:
    Sep 22, 2004
    14,487
    2,996
    0
    Location:
    Fort Lee, NJ
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    I remember the spark plugs and coolant are actually at 110-120k miles. Have you changed the engine air filter at 90k?
     
    #2 usbseawolf2000, Oct 12, 2009
  3. briand

    briand Junior Member

    Joined:
    Aug 14, 2008
    15
    0
    5
    Location:
    Charlotte, nc
    Vehicle:
    2004 Prius
    Yes, I changed it at the last oil change.
     
    #3 briand, Oct 12, 2009
  4. alfon

    alfon Senior Member

    Joined:
    May 17, 2009
    1,370
    270
    0
    Location:
    seaside, oregon
    Vehicle:
    2010 Prius
    Model:
    III
    Maybe your state has switched over to Ethanol gasoline which contain 10% ethanol. This will decrease your MPG up to 10%.

    alfon
     
    #4 alfon, Oct 13, 2009
  5. txtabby

    txtabby 2011 Prius 4

    Joined:
    Mar 26, 2007
    123
    5
    0
    Location:
    Austin, TX
    Vehicle:
    2011 Prius
    Model:
    Four
    AGH! That's my problem. I can barely get it up to 47, and still trying for 48 on this tank. I'll start using 'better' gas (Exxon, Shell, Chevron, ect.) and see what happens. I talked to a mechanic at the dealership and he told me about the ethanol. Is there anything that can make the mileage get back up to 48-50+?? Going to make sure the air filter is always clean too.
     
    #5 txtabby, Oct 13, 2009
(You must log in or sign up to post here.)