No ignition with key in "run" position | FerrariChat

No ignition with key in "run" position

Discussion in '365 GT4 2+2/400/412' started by bergxu, Jul 27, 2006.

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  1. bergxu

    bergxu Formula 3

    Aug 16, 2005
    1,305
    OnTheSerpentMound
    Full Name:
    Aaron
    #1 bergxu, Jul 27, 2006
    Hey all,

    A quick synopsis of what we recently did on a friend's '83 400i...

    -Replaced all injectors and seals
    -Replaced cap, rotor, wires and plugs

    We were having a problem with the car starting afterward, all connections double checked for accuracy, etc...everything's a-ok.

    When you crank the engine over, it fires for a split second then dies, basically when you let go of the key. So armed with a test light, we find that there's no power at B+ at the coil with the key in the "run" position. The Dinoplex has been replaced with an MSD trigger unit which is doing its job. Sooo...any thoughts on what the heck is going on here??? Something obvious we're missing?

    Cheers,
    Aaron
    '82 GTSi
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,123
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #2 Steve Magnusson, Jul 27, 2006
    Unfortunately, there's nothing to miss ;) (nor was anything you worked on directly involved).

    According to the schematic, it's a straight wire run from the 15 terminal on the ignition switch to the coil "+" terminal so you've got to look at the ignition switch end. Hopefully just a bad connection rather than the switch. It is a fairly high current stock (note the size of the wire on the schematic) and the MSD unit may actually draw an even higher current (so that adds extra stress on things in the path) -- e.g., if the "connection" shown between the two 15 terminals at the ignition switch is an unsoldered rivet sandwich you might want to add a more reliable electrical connection that doesn't rely on only mechanical forces -- just a thought...

    If you want to get it running (which I would too), I see no technical problem with adding a jumper wire (of the appropriate size) directly from the + battery terminal to the + terminal on the coil and then start using the key.

    Good hunting!

    (So everything fuel pump wise was OK?)
     
  3. laperriere

    laperriere Karting

    Mar 10, 2006
    162
    Montreal
    #3 laperriere, Jul 27, 2006
    Hi
    It reminds me a situation that I encountered, not on my 400 but on another car.
    Eventually, the problem turned out to be a wire size.
    The electrical wire (to the starter engine I think) was changed for another one with a higher section, and that was it.
    Hope it helps.
    Rgds
    Olivier
     
  4. jacques

    jacques Formula Junior

    May 23, 2006
    876
    Los Angeles/Florida
    #4 jacques, Jul 27, 2006
    I had the same problem and symtoms for years with the switch on my 1980 400i..

    two cure:..1.
    remove the entire switch and lok from the steering column and replace the black plastic module that is attached to the back of the ignition switch..smell it ..it is no doubt dead and/dying..rare as hen's teeth to find...but over the years I have taken an advanced Ferrari coarse sourcing out things for myself and "us"...Ferrari can get this piece, but...if it turns out that you need it, contact me and I'll tell you where to find it readily for approximately for about $85-$100US....Ferrari wants #250.00..I don't post my hard found sources publicly because will viciously and greedily snatch them up.. 2. The best and permanent cure is to by an ordinary four contact ignition switch and relocate it to the center console, where the darn thig should be in the first...truly a simple procedure...do you see that unused generator light dummy plug?..remove and put the new generic ignition switch in that wide oval slot..it fits so perfectly and looks right at home there..You'll love life...Now put the old asembly totally back ompletely, without the wires on it....AND...be sure to put the old key into it and unlock the anti theft deviceor the steering will lock up and you'be driving in very small circles or just straight ahead..duh..leave the key in the ingition on"on"..and enjoy..remember that the old black module regularlly toasts itself so do itNOW!!...over
     
  5. bergxu

    bergxu Formula 3

    Aug 16, 2005
    1,305
    OnTheSerpentMound
    Full Name:
    Aaron
    #5 bergxu, Jul 27, 2006
    Steve,

    I did check the fuel pumps by jumpering pins 30 and 87 on the relay connections. Both pumps are running fine and the relays are operating. Thank you for your information regarding the ignition switch! I did some further checking, after your and Jacques' advice and did find that the switch is the culprit. Jacques, I sent you a PM. Thanks again guys! Without this forum, we'd be still scratching our heads!

    By the way, once the car is up and running, how does one go about setting the fuel mixtures? I have the allen "screwdriver" to adjust them, but do I just do one bank at a time? Or adjust both a little at a time?

    Cheers,
    Aaron
    '82 GTSi
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,123
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #6 Steve Magnusson, Jul 28, 2006
    No, there's no need to somehow do the two A/F adjustments "simultaneously". If you do the 1st bank, followed by the 2nd bank, and the running conditions (like RPM) change when doing the 2nd bank, you'd have to go back and redo the 1st bank, but IME, if it's already running decently on both banks, the little tweaks at the end are fairly independent. No harm if you ping-pong back and forth a couple times just to be sure that when each bank is optimized you've got two equally-running 6-cylinders that produce the desired overall result.
     

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