Spark plug leads | FerrariChat

Spark plug leads

Discussion in '348/355' started by moretti, Dec 4, 2013.

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  1. moretti

    moretti Five Time F1 World Champ
    Lifetime Rossa Owner

    Nov 1, 2003
    59,756
    Australia
    Full Name:
    John
    #1 moretti, Dec 4, 2013
    Last edited by a moderator: Sep 7, 2017
    Sorry if this has been answered somewhere else before but I did do a search and saw nothing specific to this problem.

    I recently flooded my 355CH which is running MOTEC (guess who's car ? :p ) and I pulled the plugs and dried them out using a flame as they are Iridium, then I refitted to the car but the plug leads fell down and I'm not sure which way they should lay :(

    I have the leads on the RHS running from the unit on the RH engine bay which has numbers 1-4 on it and the leads are going from :

    1 goes to the spark plug nearest the bulkhead (this looks right due to length)
    2 goes to spark plug second from the bulkhead , and so on for leads 3 and 4.

    On the LHS I was told the spark plugs number 1-4 numbering from the rear of the car but this doesn't seem right as the leads are the wrong length for that to be right.

    The unit the leads hang from has exactly the same numbering system as the RHS (ie #1 is top left, #2 top right, #3 bottom right, #4 bottom left.

    Can anyone please let me know the correct sequence for both sides as I'm sure a lead or two are crossed as the car is backfiring when I turn it over.

    Previous owner was Satan :)
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  2. plugzit

    plugzit F1 Veteran
    Silver Subscribed

    Dec 1, 2004
    7,792
    Redondo Beach, CA
    Full Name:
    Bruce Bogart
    1-4 from the front, 5-8 from the back.
     
  3. moretti

    moretti Five Time F1 World Champ
    Lifetime Rossa Owner

    Nov 1, 2003
    59,756
    Australia
    Full Name:
    John
    Thanks Bruce, that is what I was told from my mechanic but the lead lengths don't match that information for the LHS.

    The 1-4 numbering scheme on the coil units have long leads for 1 and 2 while 3 and 4 are short for both sides which suggests that plug #1 for both sides is nearest the bulkhead ?

    This car was running fine until I flooded the cylinders as the MOTEC has been set for extra fuel on cold starts which can get exacerbated if some idiot pumps the gas pedal too much to get it started :eek:


    Happened to me before and a quick extraction of the plugs , heat the iridium electrodes, put them back in and wallah it fires up straight away, this time I drop the leads thinking they were cut to length so would be easy to fit back on but this time the car is backfiring and won't start :(

    I wrote to Rifledriver but his quota is full so posting here
     
  4. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    13,673
    San Carlos, CA
    Full Name:
    Mitchell Le
    Looking straight at the coils:

    1 2
    4 3

    7 8
    6 5

    For the plugs on the engine, looking from the back of the car at the engine:

    Firewall
    8 1
    7 2
    6 3
    5 4
    Bumper

    Good luck
     
  5. moretti

    moretti Five Time F1 World Champ
    Lifetime Rossa Owner

    Nov 1, 2003
    59,756
    Australia
    Full Name:
    John
    Thanks very much mate, that looks right to me with the length of the cables.

    The trouble I had was the the coil unit on the LHS was numbered :

    1 2

    4 3

    the same as the other side and the lead lengths were confusing.

    Again, thanks for the help, I would like to drive my car today seeing as I have a free day for a change :)
     
  6. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    13,673
    San Carlos, CA
    Full Name:
    Mitchell Le
    that is because sometimes during its life, the left one went bad and someone replaced it with the one labeled for the right side.
     

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