Fuel pump sound? | FerrariChat

Fuel pump sound?

Discussion in '308/328' started by Saabguy, Mar 19, 2025.

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  1. Saabguy

    Saabguy Formula 3

    Mar 28, 2012
    1,785
    Shreveport, LA
    Hi all,

    during my recent tries to fix things I keep going back to Fchat to read and learn first. There is a constant line in all of my research, "You can hear" or "Listen for the fuel pump to come on". I know this can't sound like a good 'ol SU fuel pump banging away but I don't hear anything nor have I heard anything in the past.

    What sound am I listening for AND could it be pumping while the damn seatbelt buzzer is going on so that I can't hear it?

    Thanks,

    Lester
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,829
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    It's that a 328 fuel pump only runs when the starter motor is cranking or the engine is actually running (the fuel pump does not run with just the key "on" and the engine not running). Both of those things are too loud to discern the fuel pump noise. In order to hear it, you need to either:
    1. Unplug the safety switch on the airflow metering device and turn the key "on", or
    2. Remove the fuel pump relay and add a jumper wire like this in the fuel pump relay socket:

    Image Unavailable, Please Login

    Then you will be able hear the soft hum/buzz of the CIS fuel pump running (with the door closed so the seat belt buzzer is not sounding ;)).
     
    Saabguy likes this.
  3. Saabguy

    Saabguy Formula 3

    Mar 28, 2012
    1,785
    Shreveport, LA
    Thank you Sir, I was concerned that my age or hearing was such that I was missing it!

     
  4. jpl

    jpl Formula Junior

    Dec 4, 2003
    368
    Yulee Florida
    Full Name:
    JP Lavigne
    Only us old carb guys can easily hear the fuel pump before the engine starts up! ;-)
     
    LE06 and MaranelloMark like this.

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