Page 3 of 3 FirstFirst 123
Results 21 to 25 of 25

Thread: SO my lofty fuel economy goals are obviously out the window.

  1. #21
    Member
    Join Date
    Jan 2019
    Location
    Earth
    Country
    United States
    Posts
    48
    Thanks
    0
    Thanked 3 Times in 2 Posts
    I got one last week, used @ 43k miles. I too was getting mid 30 mpg no matter what. After adding marvel mystery oil in the gas and oil (and changing oil) I didn't see an improvement. But I slowly pushed the gas pedal to the floor a couple times and kept it like that til I was doing 80+ from 40mph. Now it's much better. I assume it was driven very nice and never went into higher rpm's. Stuff will gum up over time and if you don't get rpm's high it will never get the sludge off. Of course you will probably need a system cleaner of some sort in the system. I thought there was something wrong but I think it was just never opened up on the highway.

    FWIW, the "normal operating temperatures" given to cars is there for a reason. At ambient temps, the pistons are slightly smaller, then when the car is warmed, the pistons swell ever so slightly, thus meeting the intended tolerances for the engine. Until it's warmed up the piston has very slight lateral movement at a microscopic level. This is why engines experience the most wear at startup, a piston will "rattle" in the cylinder vs sliding. It's best to warm it up, and as the manual states, when the green temp icon disappears, it's warmed to operating temperature.
    Physics and all..



  2. #22
    Member iriegnome's Avatar
    Join Date
    Oct 2018
    Location
    Wisconsin
    Country
    United States
    Posts
    35
    Thanks
    50
    Thanked 18 Times in 8 Posts
    I feel you on this one. My avg mpg was about 47mpg in the fall. I bought my 2018 in October. I drive 100 miles per day. Great mileage. Then it got cold. My average is down to 41.6 mpg. And my daily goes as low as 35 mpg because I have to run the heater enough to keep the windows from fogging up.. BTW, this is not a great car for defrosting country here in the upper mid-west! Also, I started getting worse gas mileage after I took my car to the dealership for my first (and free) oil change.

  3. #23
    Senior Member Fummins's Avatar
    Join Date
    Oct 2016
    Location
    Wild Rose Country
    Country
    Haiti
    Posts
    2,107
    Thanks
    818
    Thanked 1,079 Times in 683 Posts
    Have you checked your oil level to see if they over filled it? They like to do that sometimes. Or maybe threw in 5w20 or 5w30? I'd hope you're dealer is brighter than that but I know the dealer closest to me isn't.

  4. #24
    Administrator Daox's Avatar
    Join Date
    Jan 2013
    Location
    Germantown, WI
    Country
    United States
    Posts
    4,701
    Thanks
    2,610
    Thanked 1,530 Times in 889 Posts
    Quote Originally Posted by iriegnome View Post
    ...I have to run the heater enough to keep the windows from fogging up.. BTW, this is not a great car for defrosting country here in the upper mid-west!
    A grill block totally fixes that IMO.
    Custom Mirage products: Cruise control kit, Glove box light, MAF sensor housing, Rear sway bar, Upper grill block

    Current project: DIY Nitrous oxide setup for ~$100

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage DE 1.2 manual: 45.4 mpg (US) ... 19.3 km/L ... 5.2 L/100 km ... 54.6 mpg (Imp)


  5. #25
    Senior Member
    Join Date
    Aug 2017
    Location
    Richland Center
    Country
    United States
    Posts
    1,284
    Thanks
    2
    Thanked 431 Times in 333 Posts
    Quote Originally Posted by iriegnome View Post
    I feel you on this one. My avg mpg was about 47mpg in the fall. I bought my 2018 in October. I drive 100 miles per day. Great mileage. Then it got cold. My average is down to 41.6 mpg. And my daily goes as low as 35 mpg because I have to run the heater enough to keep the windows from fogging up.. BTW, this is not a great car for defrosting country here in the upper mid-west! Also, I started getting worse gas mileage after I took my car to the dealership for my first (and free) oil change.
    I see about a 5 mpg difference between summer & winter. I would say my numbers are about 47 summer & 42 winter, too. February was exceptionally cold this year. Had some tank fill ups around 40 then. Adding an engine block heater helps the inside of the car warm up better, too.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •