348 problem today | FerrariChat

348 problem today

Discussion in '348/355' started by angelis, Aug 29, 2005.

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  1. angelis

    angelis F1 Veteran
    Owner

    Jun 18, 2004
    6,395
    London, England
    Full Name:
    Sy
    After a hard run and lots of driving in hot weather, as I was driving home......I could'nt rev more than 3,000 rpm, no matter what gear i was in.

    Car could'nt go more than 50 mph. Lasted for about 2 miles.

    Then, the alternator light came on....and the car started running normally.

    First time it's happened....any ideas what it could be.

    As I said, it was a hot day and I'd been driving it hard.
     
  2. No Doubt

    No Doubt Seven Time F1 World Champ

    May 21, 2005
    72,740
    Vegas+Alabama
    Full Name:
    Mr. Sideways
    Snapped the alternator belt?? Overheated the cats (i.e. "slowdown" feature)??

    What trouble codes do your ECU's report?
     
  3. angelis

    angelis F1 Veteran
    Owner

    Jun 18, 2004
    6,395
    London, England
    Full Name:
    Sy
    How do I find that out?

    Could be overheated Cats, but would it stop the car from going over 3,000 revs?

    Cars running fine now.
     
  4. No Doubt

    No Doubt Seven Time F1 World Champ

    May 21, 2005
    72,740
    Vegas+Alabama
    Full Name:
    Mr. Sideways
    To check the codes, press the red button next to each of your ECU's (just behind your seat there is a carpeted cover that easily comes off by turning 6 "screws" a half turn a piece - once off, you'll see both ECU's).

    That will flash your Check Engine light on your dash for each ECU. Count the flashes in sequence. Flash, Flash, Flash, Flash, pause is 4, flash, pause is 1, so 4111 would be flash, flash, flash, flash, pause, flash, pause, flash, pause, flash, pause, long pause.

    Do this with the engine running. You'll probably see the same code repeated several times before a new code is displayed.

    Now, as for your cats overheating, typically you would have seen a "slowdown 1/4" or "slowdown 5/8" light...then the 348 ECU's switch off half of your engine so you are only running on 4 cylinders (to cool the cats) at any given time.

    Real cat overheating is dangerous, but typically just caused by an A/F ratio that is too rich (easy to adjust via the screw under each blue cap on your MAFs).
     
  5. Ken

    Ken F1 World Champ

    Oct 19, 2001
    16,078
    Arlington Heights IL
    Full Name:
    Kenneth
    Sounds like a fuel delivery problem to me. Did you try a lower gear? If so and you went slower, then that's likely it.

    Fuel line, fuel filter, fuel pump, FUSES for fuel delivery system; you have a bunch of 'em I think.

    Ken
     
  6. angelis

    angelis F1 Veteran
    Owner

    Jun 18, 2004
    6,395
    London, England
    Full Name:
    Sy
    Someone just told me it's probably the cats overheating and shutting down half the engine.

    The car was getting hot............
     
  7. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner


    Sy - Normally, you'd get a slow down light when that happens. But, the P.O. of your car might have pulled the bulbs if he experienced similar problems. When you "key on", do the the "slow down" lights illuminate on the dashboard briefly?
     
  8. angelis

    angelis F1 Veteran
    Owner

    Jun 18, 2004
    6,395
    London, England
    Full Name:
    Sy
    Dan, one slow down light comes on but the two check engine lights don't.
     
  9. BT

    BT F1 World Champ
    Lifetime Rossa

    Mar 21, 2005
    15,291
    FL / GA
    Full Name:
    Bill Tracy
    The one slow down engine light is usually from a sensor in one of the cats. It could be an O2 sensor, the thermocoupler, a catalytic converter going bad, or and ECU malfunction. You can switch the sensor from one side to the other if you are getting the slow down light staying on and see if it switches to a slow down 5/8 instead of a slow down 1/4 for example. If it is happening only after running for a long distance you may have a rich fuel mixture that is getting too much fuel in the cat and getting overheating from burning too much fuel in the catalytic converter. I have had a few slow down lights come on, usually after at least a half hour running and usually only when I am running very hard.
    BT
     
  10. jjstecher

    jjstecher Formula Junior

    Jan 21, 2002
    962
    Rochester Minnesota
    Full Name:
    John Stecher
    I had this happen multiple times before. Each time for me it was the alternator went bad. The car will not run about 3000 RPM's as my understanding is that the battery cannot keep up with the demands on the ignition system above that speed.

    Typically what would happen to me is that the car would hit 3000 RPMs and not go above it, shortly afterwards the battery light comes on and you have about 5 minutes to get home before she completely drains.

    Needless to say I have gone through 3 alternators in 4 years now but I do track the car a lot more than usual and its the heat and RPM's that eats the early Delco units. Good thing Napa has a lifetime replacement policy. :)
     
  11. angelis

    angelis F1 Veteran
    Owner

    Jun 18, 2004
    6,395
    London, England
    Full Name:
    Sy
    Exactly the problem I had.

    Although my battery is ok and the car powers up.
     
  12. Ken

    Ken F1 World Champ

    Oct 19, 2001
    16,078
    Arlington Heights IL
    Full Name:
    Kenneth
    Wow, that's a LOT of alternators! Isn't there something more heavy duty that will stand up to racing?

    Ken
     
  13. PassionIsFerrari

    PassionIsFerrari Formula 3

    Aug 15, 2004
    2,454
    Do you have a U.S. car...If so, both Slow Down Lights and both Check Engine Lights should come on at the 'on' position and at start-up...If they don't, this either means a bulb has burned out or someone has removed these bulbs. DO NOT DRIVE THE CAR until you verify this. Overheating cat's can and will cause an engine fire...Make sure all your electrical connections are clean, use Stabiliant 22A or contact cleaner (radio shack). Bad connections will cause faulty readings from the ECU. This is a simple way to cure problems but I have a hunch that yours is of deeper concern.
     
  14. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    I'm guessing that's the "missing link" in this equation. My diagnosis? Hang on folks -- it's going to get bumpy here:

    1. Previous owner had trouble too
    2. Got tired of the slow down light and loss of power
    3. Removed bulb
    4. In fact, the cat ECU was failing (and continues to fail) when hot

    Pull binnacle, replace bulbs
    Ensure lights come on with Key-On
    Drive hard, make it lag again
    Which Slow Down Light is blinking?
    Swap ECU's from side to side to figure out which one is bad
    Replace ECU.


    or.... method #2:

    Remove cats
    Remove cat ECU's
    Install test pipes
    Drive like a madman.


    (This is not a formal endorsement of any particular mechanical or emissions practice. Always seek the advice of a professional)

    :)
     
  15. angelis

    angelis F1 Veteran
    Owner

    Jun 18, 2004
    6,395
    London, England
    Full Name:
    Sy
    It's a UK car.

    I can confirm that both slow down lights are working.

    The two check engine lighst don't work, howver the manual states they are not used.

    Looks like it could be the Alternator about to go or an electrical fault.
     
  16. jkuk

    jkuk Formula Junior

    Nov 3, 2003
    259
    Wirral, UK
    Full Name:
    John K

    If its the alternator you can get it rebuilt in the UK for about £100.

    Mine went up in smoke - the red light on the dash is a dead give away.

    Mine was the Nippondenso unit - late '91 model
     

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