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Premium Fuel

Discussion in 'Performance & Fuel' started by duck44, Dec 13, 2009.

  1. duck44

    duck44 New Member

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    My 6.2 gas cover "recommends" premium gas. What will happen if I do not use premium is it more for performance or longevity of the engine?
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  2. Chris Miller

    Chris Miller New Member

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    Depends on the model. Some say you must use premium gas but still fun fine on 87. Others will knock and cough like the devil. Just put about 1/4 tank of 87 in and see how it runs. If it runs badly, just top it off with 93 and it should be okay.
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  3. unplugged

    unplugged New Member

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    Lower octane fuels don't do the damage. Detonation is the culprit. The engine is equipped with a knock sensor. It will adjust the timing to allow use of lower octane fuel. If you experience pinging under load just go light on the throttle. If you don't want to compromise performance then fill with premium gas.
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  4. brianj

    brianj New Member

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    I do not know how much, if any, alcohol they run in fuel in Texas, but I can tell you that 87 octane fuel , mixed for a winter blend in new england, plus ten percent alcohol we have to run, makes most knock sensor equipped trucks turn into slugs once the computer pulls all the timing out to prevent detonation.
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  5. DAREDEVIL

    DAREDEVIL New Member

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    THIS IS 1000% corect !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    Follow this post and u be fine !:great::glasses:
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  6. Viper

    Viper New Member

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    it could also cause misfires and it is possible to cause unreverisble damage when using the incorrect grade of fuel, however unlikly still possible
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  7. duck44

    duck44 New Member

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    I have run 2 tanks of Premium and the gas mileage did increase to 15.5 from the upper 12's. I don't know if this is due to the break in period so I can not say that it runs any different. At 2700 miles now.

    Thanks,
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  8. TRPLXL2

    TRPLXL2 New Member

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    Oddly enough I have a 90' Lumina eurosport with the 3.1 multiport, and it has the same sticker on the inside of the gas filler. We tried a tank of 87 in it one time, and the engine ran horrible. Erradic idle, misfired, and surged under load. Took it home and syphoned the gas out, and filled it back up with Premium 93 and it ran fie ever since.
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  9. Gmcsuvguy

    Gmcsuvguy New Member

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    I run premium in my 6.2L...I also did an "experiment" on my Yukon, I ran premium for a few tanks and ran regular for a few tanks doing the same type of driving and I got about 4.5 mpg better with premium. The cost pretty much worked out to be the same, better mileage for more initial cost compared to less mileage with less initial cost...plus the premium is that much better for your engine. I run premium all the time now.
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  10. Stealth

    Stealth New Member

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    chances are that the computer in that is not as good as modern trucks, and that's why it ran so poorly
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  11. Chad01

    Chad01 New Member

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    Follow what the manufacturer states. The higher octane fuel is set in relation to the compression ratio. The manufacturer knows what they're talking about...
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  12. scrappiedew1

    scrappiedew1 New Member

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    i had knew a guy that had a mitsubushi 4dr montero and was to run premium in it but always run 87 octane he kept messing up his o2 sensors .. but that was a mitsu .. not a amerian engine you could try the 89 octane
    #12

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