What is the difference between an SFI and MFI rating on an engine description?

I own a 2004 Ford Focus SVT and I am curious to know what the difference is and which would be better, considering my particular model is the only 2004 SVTF with MFI.


well, i finally found a website that is in regards to the SFI vs. MFI question and the claim is that SFI is better. I believed this to be true, considering the Zetech model comes with the SFI rating also, and is the sportiest of all options for the 04 Focus 3dr Hatchback - thanks for the help.

Also, the link is as follows for anyone else interested in knowing the answer:


4 Answers

  • 1 decade ago
    Favorite Answer

    With MFI all injectors squirt at the same time. For SFI they squirt sequentially at the optimum time for each cylinder.

    It is much easier to troubleshoot specific cylinder or injector problems with SFI because the ECU can cut out one injector at a time and the one that does not drop engine speed is the problem cylinder. MFI can't do that since they all trigger at once.

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  • 1 decade ago

    SFI-Sequential Fuel Injection

    MFI-Multi-port Fuel Injection

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  • pattie
    Lv 4
    4 years ago

    That's a tricky question..

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  • Anonymous
    4 years ago

    Thanks for the answers.

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