very low mileage in city AND highway...why?

Discussion in 'That'll Buff Right Out' started by Mojo, May 26, 2005.

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  1. Mojo

    Mojo New Member

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    "bigdogg" is a douche...

    vbmenu_register("postmenu_36552726", true);


    the owners manual recommends 86 or higher gasoline. i often fill up with 76's regular 87 pump gas and probably 89 once a week. but now that in california, its gotten pretty heated (80-85 degrees), i have been getting very low gas mileage (my fathers suv litterally gets more mpg than my civic :argue: ) could it be that the intake piping is so heated to the point where i cannot hold my hand on it for 10 seconds?

    my driving habits are usually spirited (never race, i only go up to 5.5k rpm at most to merge on the highway).

    my best educated guess would be that i have been going on the highway often more than the last few weeks. i cruise @ approxmiately 65-70 mph with light traffic. any of you could help me out and explain to me any possiblities why im getting such low MPG all of sudden, please enlighten me :)
     
    Last edited: Jun 6, 2005
  2. because you are asking in the wrong section, dumbass
     
  3. e r y k

    e r y k New Member

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    :rofl:
     
  4. Y2kAccord

    Y2kAccord Everything happens for reasons I just dont know

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    bad mileage in a Civic is driving habits.. I drove mine hard and still got 25mpg around town though
     
  5. illeagle94

    illeagle94 New Member

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    I have an 04 Si. My fuel light is on now, and I just passed 300 miles on this tank.

    I may go get gas now, so I can calculate my MPG.

    27.6 MPG was the result.
     
    Last edited: May 26, 2005
  6. Alternative

    Alternative Guest

    You have to drive really carefully in a petrol powered car in order to get good fuel economy. I hope you are not driving like you have a sports car, so if you are, slow down.

    ANd highway fuel economy will go down as your speed goes up. The ratings are determined while going at speeds of like 55mph for highway, I think?

    You may as well just buy a diesel if you are worried about fuel economy. :mamoru:
     
  7. p00tan6

    p00tan6 New Member

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    aem short ram intake
    catback exhaust
    test pipe (catless)
    *CEL is light on due to catless* (aka malfunction indicator lamp)



    I would get rid of all those things. You're emissions isnt running right which could cause bad gas mileage.
     
  8. vbp6us

    vbp6us New Member

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    One must ask...why do you have those mods in an automatic civic anyways? Btw...catless cars have better gas mileage so that can't be it.
     
  9. bonylad

    bonylad You are all so very predictable.

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    Your dumping fuel. The PCM is not reading a cat. As such is in a predetermined fuel map. A "safe" map. That added to the fact that you obviosly dont drive for economy adds to your crappy mileage.
     
  10. bonylad

    bonylad You are all so very predictable.

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    Actually it is the problem. The sad fact alot of people dont know is modern cats are NOT restrictive. They are already high flow. The old idea of gutting a cat because it was restrictive was true at one point. Now its just not the case. Add in the fact that the car is tuned to see readings from before and after it, now it doesnt see any differences. It sees the cat as failed, and causes a DTC to set. Therefore into a preset map in the PCM.

    On a stock car it would be bad enough. This guy has his modded.

    This isnt an old carbed Ford here.
     
  11. LovEyDuBB

    LovEyDuBB OT Supporter

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    doesn't installing a testpipe cause less back pressure? don't NA cars need some backpressure?
     
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