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  1. #1

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    compression testing and efi

    was wondering when checking compression on a 04 gpr,holding throttle wide open plugs in caps. would the cases get full of fuel ?does the fuel pump pump fuel as soon as you press start button?


  2. #2
    here`s what you do:

    take all the plug wires off the plugs and rest to the side making sure it is NOT near any metal.
    only take the plug out on the cylinder your going to test, then put that plug back and onto the next, etc...

    get your max highest pressure reading for each cylinder, it should only require a few seconds of cranking.
    Yes there will be fuel going into the cases/cylinders but not enough to worry about for an accurate compression test...
    Hope this helps...

  3. #3
    fenn's Avatar
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    he got it..just make sure you hold the throttle wide open

  4. #4

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    just wasnt sure if it wasnt running if it would flood the engine with tons of fuel

  5. #5
    "Hustler" Inkaddict's Avatar
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    Quote Originally Posted by don jordan View Post
    just wasnt sure if it wasnt running if it would flood the engine with tons of fuel

    Fuel cuts on a efi GPR when held at WOT when not running...

  6. #6

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    well thats good to know as i have two heads to check. thanks fo the info

  7. #7
    Happily Self-Employed WFO's Avatar
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    Quote Originally Posted by Inkaddict View Post
    Fuel cuts on a efi GPR when held at WOT when not running...
    it may do that too, but for sure it wont spark at WOT, so dont worry about the plug wires arcing

    I know TJ

  8. #8
    "Hustler" Inkaddict's Avatar
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    Quote Originally Posted by WFO View Post
    it may do that too, but for sure it wont spark at WOT, so dont worry about the plug wires arcing

    I know TJ


  9. #9
    Quote Originally Posted by Inkaddict View Post
    Fuel cuts on a efi GPR when held at WOT when not running...
    my plugs were soaked when I was recently testing mine with the new head.
    and I was holding WOT...

  10. #10
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    Quote Originally Posted by Pale Rider View Post
    my plugs were soaked when I was recently testing mine with the new head.
    and I was holding WOT...
    Maybe Im wrong... Was it still winterized??

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