CSFI to MPFI conversion identification

Discussion in 'Tech Info' started by HankHill, Sep 16, 2011.

  1. HankHill

    HankHill Member

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    Hi -

    Is there an easy & positive visual inspection method to determine which injection system is currently installed? I don't have maintenance records from the previous owner, so I don't know which system is in my '00 Tahoe.

    I tried to search, but didn't have any luck.....

    HH
     
  2. gpracer1

    gpracer1 Full Access Member

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    The only way I could think of is to open the throttle body butteryfly (or remove the TB) and shine a flashlight in there. If the 8 fuel lines go into the manifold with two little rounded clips sticking out, then that is the old style. The new style will just be the line/injector going into the manifold with nothing else visible since it does not have the external clips.

    You might need a mirror to get in there and see it.
     
  3. SunlitComet

    SunlitComet OBS Jedi-Do Good

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    take off your injector harness and look down in the connector pit which picture looks like yours? See the difference in the holes above each line? One dot the other t-shaped?
     
    Last edited: Jun 5, 2012
  4. sparg93

    sparg93 Expedition Tahoe

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    what year did they start with the new style? what is the benefit?
     
  5. SunlitComet

    SunlitComet OBS Jedi-Do Good

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    it was started around 2003 I believe. At least that is when GM started sending out letters to owners. Injector is taken out of body and new type is installed downsteam of each line. No more poppet junk. Cleaner burning fuel, smoother idle, and what not. Comes with new regulator installed.


    OLD
    [​IMG]


    NEW

    [​IMG]


    Got MPFI?
     
  6. sparg93

    sparg93 Expedition Tahoe

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    Interesting...my rig runs really smooth, but i know i have a slight spider leak on both banks...i avg ~15.5mpg.

    Worth the upgrade?
     
    Last edited: Oct 12, 2011
  7. SunlitComet

    SunlitComet OBS Jedi-Do Good

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  8. sparg93

    sparg93 Expedition Tahoe

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    i hate to ask this...but for $250, what do you think the benefit is for me? (assuming the above extra intel i provided)


    My truck runs really smooth and my mileage is decent for 4dr 4x4 with 1.75" lift & 33" tires.
     
  9. SunlitComet

    SunlitComet OBS Jedi-Do Good

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    I guarantee it will have to be done eventually so do it before it suddenly decided to start acting up. And no spider leaks. so if you leak now you will probably get some performance and mileage back.
     
  10. sparg93

    sparg93 Expedition Tahoe

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    I have a BB tune and recently lowered the thermostat...should i sent the computer out to be adjusted if i also do this upgrade?

    you're right...i also need to replace the intake manifold gasket and while everything is off, i might as well do this too.

    ---------- Post added at 09:29 PM ---------- Previous post was at 09:16 PM ----------

    any idea the difference between the AC Delco & Delphi Unit?
    http://www.amazon.com/ACDelco-217-3...hevrolet|47&Year=1999|1999&newCar=1&carId=002
     

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