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I have a 2000 Mercury efi saltwater engine 250hp that is using well over a gallon of gas per mile-have changed all filters,high end fuel pump,strator and plugs-it seems to surge some at low speed and tops out at 5100 rpms now-had both oil and fuel filtered-any help would be good-thank you,David

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  • Anonymous Mar 22, 2014

    Engine idles ok slight roughness runs good at top end But mid range speed it's rough and cuts out but will pick back up without completely shutting down


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Sounds like a problem with your injector or injector sensors. One of the nice things about the EFI`s are the ability to hook up a diagnostic unit to the motor and then a tech at a merc dealership would be able to tell you exactly which sensor or injector is the problem

Posted on Apr 14, 2009

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