Dumb question - how to adjust the idle speed on a 328 | FerrariChat

Dumb question - how to adjust the idle speed on a 328

Discussion in 'United Kingdom' started by F328GTS, Jul 5, 2004.

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  1. F328GTS

    F328GTS Formula 3

    Apr 27, 2004
    1,628
    Cambridgeshire, UK
    Full Name:
    Nigel R
    As you can probably tell by the title I don't do technical, but I do need to adjust the idle speed on my 328 as it is running way to fast (1,500 rpm). I have located the idle adjusting screw by looking in the handbook, see first photo attached. Now the question is, how do you turn it? The manual doesn't tell me that!

    Secondly, somebody else I spoke to said to adjust the brass bolt under "the elephants trunk", as this will also adjust the idle speed. This bolt can be seen in the second photo, but the manual says this is the By-pass screw. What is the purpose of this bolt, and should I leave it alone?

    Thanks in advance.
     
  2. stevew

    stevew Formula 3

    Jun 9, 2002
    1,839
    uk
    Full Name:
    Steve
    F328 GTS

    The screw on the left of the throttle body is the throttle butterfly adjustment screw,this is normally preset at the factory,however if yours has been altered then is all you need to do is remove the large hose and set the butterfly flap gap to 0.003" with this screw.The idle is adjusted with the large brass By-Pass screw.Just turn it by hand.It is probably worth checking the mixture once you have reset the idle.
    This is the procedure that I use for my 308QV.I presume it is the same for the 328.

    Hope this helps

    Steve
     
  3. F328GTS

    F328GTS Formula 3

    Apr 27, 2004
    1,628
    Cambridgeshire, UK
    Full Name:
    Nigel R
    Thanks Steve, adjusting the large brass By-pass screw has done the trick.
     

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