355 F1: weird gearbox symptoms | FerrariChat

355 F1: weird gearbox symptoms

Discussion in '348/355' started by ze_shark, May 28, 2017.

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  1. ze_shark

    ze_shark Formula 3

    Jul 13, 2003
    1,274
    Switzerland (NW)
    I have had my 98' 355 GTS F1 since 2001 so I know the car well.

    Taking it out of winter storage, i immediately noticed something weird:
    - at first priming, the whirring sound of the pump sounded very slightly wobbly before settling on its normal frequency
    - then during the first miles, shifting from 1st to 2nd was faster than usual, unchararectistically abrupt
    - then the car missed a shift between 2nd and 3rd (ghost neutral) before catching itself
    - a few miles later, it did it again, missing an upshift from 3rd and going straight to 5th, then refusing to downshift from 6th. I found myself coasting off the highway, unable to downshift. Once stopped I could re-engage first, upshift normally and drive home.

    No warning light on the dash, never had such an occurrence before.

    Any pointers ?
     
  2. taz355

    taz355 F1 Veteran
    Owner Silver Subscribed

    Feb 18, 2008
    5,942
    Indio Ca/ Alberta
    Full Name:
    Grant
    Original pump?
    If so how many flashes to prime.

    If this is all good engine mounts worn. When and how many km on the mounts.
     
  3. taz355

    taz355 F1 Veteran
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    Feb 18, 2008
    5,942
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    Grant
    Motor could be going.

    My guess is engine mounts if your gearbox is in good order mechanically.

    Maybe some air in line so a small leak.

    Try shifting it many times without motor running and see if ot shifts good.

    Look at cross member under actuator see if it has rubbed.

    Only time i have had false neutrals was when engine mounts worn and actuator rubbing.
     
  4. ze_shark

    ze_shark Formula 3

    Jul 13, 2003
    1,274
    Switzerland (NW)
    1998 GTS F1 with 62'000km, nothing's been replaced yet in that area, including the clutch.
    9 flashes to prime then the pump keeps going for a total of 16 seconds.
     
  5. phrogs

    phrogs F1 Veteran
    Silver Subscribed

    Apr 13, 2004
    7,113
    Michigan
    Mine stops flashing as the pump turns off but with a brand new battery I'm at 18 seconds to prime.
     
  6. taz355

    taz355 F1 Veteran
    Owner Silver Subscribed

    Feb 18, 2008
    5,942
    Indio Ca/ Alberta
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    Grant
    Those are both good at 9 or 10 flashes but pump should shut off shortly after last flash.

    Did you try shifting lots without motor running and see if it false neutrals??

    If original motor mounts my guess is they are shot, this causes binding and getting false neutrals sporadically.
     
  7. ze_shark

    ze_shark Formula 3

    Jul 13, 2003
    1,274
    Switzerland (NW)
    Strange, as far as I can remember, the thing has always stopped flashing (and allowed me to select Neutral to start the car) before the pump was done priming.

    I did try to do shifts with engine off. Never done this exercize before so not sure what to expect. I kept doing 1st-N-1st-N, but sometimes I got 2nd instead of N.

    Shot engine mounts would be coherent with a symptom that appears suddenly after winter storage. Car is due for belts so it is the right time to have them done.
     
  8. taz355

    taz355 F1 Veteran
    Owner Silver Subscribed

    Feb 18, 2008
    5,942
    Indio Ca/ Alberta
    Full Name:
    Grant
    Yes as soon as light quits flashing you can shift and pump runs briefly but in your case if you shift to neutral while engine off pump may run a few seconds longer so that would be corrct
     
  9. ze_shark

    ze_shark Formula 3

    Jul 13, 2003
    1,274
    Switzerland (NW)
    An update on the problem: impossible to connect a Ferrari tester (tried two), the gearbox ECU (PN 174526) refuses to communicate and reveal the content of its fault codes memory, but somehow continues to function, albeit not as well as it used to.

    Tricky problem given the fact that
    - the ECUs are not available as spares and therefore solidly expensive on the grey market
    - I don't even have certainty that the ECU is at fault, only that it refuses to communicate. Could be a sensor or actuator that throws it off.

    Started looking for a fellow 355F1 owner who would agree to do a quick swap to see what the problem is about. Oh joy ...
     
  10. WATSON

    WATSON Two Time F1 World Champ
    Owner Rossa Subscribed

    Sep 9, 2010
    21,611
    WI
  11. Dave rocks

    Dave rocks F1 World Champ
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    Nov 23, 2012
    16,047
    Orchard Park, NY
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    Dave Lelonek
    Given you are in Europe - did your techs connect the SD directly to the F1 TCU?

    I ask this for two reasons:

    1) If using the OBDII port, it's possible that Euro cars A) don't communicate to that ECU thru the OBDII port, B) The test socket of the F1 ECU is unplugged from the can line going to OBDII socket.

    Also, what "Ferrari tester" did they use?
     
  12. ze_shark

    ze_shark Formula 3

    Jul 13, 2003
    1,274
    Switzerland (NW)
    Yes, they connected the Ferrari tester directly to the TCU and it is not responding, cannot be interrogated for fault codes, furtherless go back through the apprentice mode (seems there is such a thing), or support a purge of the hydraulic system. Power rails are normal.

    I understood that there is also a digitec (sp?) box sitting in between the Motronic ECU and the TCU, this one works fine.

    It still works kind of, can select gears, go back to neutral, but it goes very abruptly into gear from 1st to 2nd and often misses 2-3 and goes into N instead. Came out of the blue on the first miles of the first day of my 16th season with this car.

    The TCU (part 174526) is listed for 1200€, but unavailable, neither in the network nor at all parts suppliers i have found so far on both sides of the pond.

    I imagine that there is inside
    - a microcontroller
    - some kind of serial interface chip for coms with the SD tester
    - interfaces for the various sensors and actuators the TCU drives/reads
    so possibly a low tech problem, but not trivial to solve without schematics and a solid understanding of how the TCU is supposed to normally behave.
     
  13. Dave rocks

    Dave rocks F1 World Champ
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    Nov 23, 2012
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    Which "Ferrari tester" did they use? This is an important questions - please find out specifically what they are using.

    Can you get them to make a video?

    See this video I made for reference:

    [ame]http://www.youtube.com/watch?v=S4AIk-DPNW8[/ame]

    It would be wise for them to check there ISO extension cable to be sure it's working..
     
  14. taz355

    taz355 F1 Veteran
    Owner Silver Subscribed

    Feb 18, 2008
    5,942
    Indio Ca/ Alberta
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    Grant
    I take it engine mounts are good and actuator is not rubbing on the cross member?
     
  15. ze_shark

    ze_shark Formula 3

    Jul 13, 2003
    1,274
    Switzerland (NW)
    Engine mounts checked when engine was taken out a month ago to do the belts.
     
  16. phrogs

    phrogs F1 Veteran
    Silver Subscribed

    Apr 13, 2004
    7,113
    Michigan
    It Flashes 11 times on mine.
     
  17. WATSON

    WATSON Two Time F1 World Champ
    Owner Rossa Subscribed

    Sep 9, 2010
    21,611
    WI
    As another reference mine flashes 4 times from cold

    (new 360 pump motor and accumulator bulb)
     

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