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  1. #61
    I live far away. WarStryker13's Avatar
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    Default Re: Bad gas mileage help

    Did you replace the upstream o2?

    Derp- I read back and saw that you did. Lol

    Handling upgrades, go-slow parts, and an attitude.

  2. #62
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    Default Re: Bad gas mileage help

    I did ..my long term fuel trim is still -10 idle and -16 at throttle, while short term is +5 to -5 ish.
    Vac is at the -18 to -21 ish on the torque app.
    Now i guess would be the fuel pressure to check next as soon as i get a tester.
    I thought it could be fuel leak but my friend said i would smell fuel under the hood, also doesnt mean it cant be leaking else where down the line under pressure?.
    A weak pump wouldnt cause more fuel consumption would it. I put a screwdriver up to the injectors and heard them pulsing, the same ticking. But that still doest mean that they are the same pattern, if that would even relate to my issue.
    I have had a thought about the plugs i did about 3-4 months ago might be fouled or something.

  3. #63
    I live far away. WarStryker13's Avatar
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    Default Re: Bad gas mileage help

    As long as LTFTs aren't beyond -16.4/+16.4, the fuel system is not malfunctioning.

    Handling upgrades, go-slow parts, and an attitude.

  4. #64
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    Default Re: Bad gas mileage help

    Ideas on any other culprits

  5. #65
    Killa Bee Scottydoggs's Avatar
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    Default Re: Bad gas mileage help

    im currently enjoying the longest lasting tank of gas ever. not trying to rub it in at all. im the king of crap mpg. all local stop and go, dic says i do 12 mpg on avg. or less if im beating on it.

    but i think my gas was evaporating on me due to a line being off the top of the tank and the pump was not sealed properly. yes i could smell gas some times. i filled it to the top after fixing it, that has to be a month ago and i still got 1/2 a tank left.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, 2.8, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW

  6. #66
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    Default Re: Bad gas mileage help

    I will investigate this weekend...hopefully there is the hatch underside of the back seats

  7. #67
    I live far away. WarStryker13's Avatar
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    Default Re: Bad gas mileage help

    Huh. My filler neck is looking nasty, probably a few other things that aren't pretty up in there... Now I'm gonna have to check that out myself.

    FYI, if your 05 is like my 04, you don't need to remove the rear seat to get to the fuel tank trap door, just fold them down and there'll be a dashed-line kind of cut from the factory under the trunk carpet pad, in the thin base layer of carpet. It'll mean cutting carpet, but it's alot faster than pulling the entire rear seat out, and you can still cover the cut portion with the trunk carpet pad.

    Handling upgrades, go-slow parts, and an attitude.

  8. #68
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    Default Re: Bad gas mileage help

    Seems the 05 is like...well like the milk mans kid when it comes to some of this stuff

  9. #69
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    Default Re: Bad gas mileage help

    I will look tho for sure

  10. #70
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    Default Re: Bad gas mileage help

    Ok i dont know if im trippin or not..
    The car seems fine for the most part but
    (First)When i take off onto the highway the car revs high from 1st to 2nd. Like 4-5grand. Normal? Or me just hitting the gas peddle a lil more then I should be or maybe part of the tranny issue i have

    (Second). On a longer trip i can the gas level go down as i drive. No problem but when i park it (on a level surface) i check the gas level and when i go back later to go out it starts, some times grumpy but starts every time. Turns over nicely, seems to catch good but rumbles a bit when it starts. Does or can something cause more consumption starting like that.
    I still havent checked for the hatch for the gas tank under the seat nor do i have a fuel pressure gage, i was sure you might have asked me if i have done this yet but life is hectic and has been raining a lot.

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