575 Random/Multiple Misfire | FerrariChat

575 Random/Multiple Misfire

Discussion in '456/550/575' started by plip, Oct 6, 2017.

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  1. plip

    plip Formula Junior

    Aug 25, 2003
    285
    Switzerland
    Full Name:
    Gianni Olivieri
    Hi

    Because of very intensive abroad traveling have almost not moved the car this summer. Last week, finally, a couple of days off. Start the car, drove to the petrol station, filled her up and off went but....check engine line on soon after refilling. Visited the local Ferrari shop which diagnostics engine misfire. Have got the same issue few years ago when the intake manifold gasket failed and was replaced with an update version, but was not the case this time as the gaskets seem to be be fine. The codes were deleted, drove the car without issue and then went to Italy for a few days. On the way back, after 850 Km (most of which driven the 'proper way'), again check engine light on. This time hooked my own OBD2 reader and get:

    P0300 Random/Multiple Cylinder Misfire detected. Scrolling down i get:

    P0301 Cylinder 1 Misfire Detected
    P0302 Cylinder 2 Misfire Detected
    P0307 Cylinder 7 Misfire Detected

    Would not consider been a problem with spark plug since happening in more of one cylinder at the time. Any idea where should start playing with spanners ? Ah incidentally the Ferrari dealer mentioned that it could be the Motronic abt to die....sincerely hope not!

    Tks for any help

    Best
    Gianni
     
  2. zstyle

    zstyle Formula Junior

    Jun 28, 2007
    531
    Fountain Hills
    Full Name:
    Jon
    You could find a shop with a smoke machine and inject smoke into the intake plenum to check for leaks. You say the manifold gasket failed yet which one? One for the side baffles or the one between cylinder head and runners?

    You could easily pull spark plugs, check gap (depending on the plug installed), and observe color of plug. Hopefully they will all look the same.

    Another problem we have seen in Arizona is injector malfunction and also fuel pump problems (due to the ethanol in the fuel and owners leaving cars sit for long periods of time). The fuel in the dessert lasts about 3 weeks then starts to separate. We always recommend owners to leave cars as close to empty as possible if not driving for a few months or fill up with race type gasoline to keep fuel stable for longer periods.

    Sometimes all you need to do is disconnect the harness to coil-on-plug and reconnect. If you do pull plugs, check the spark plug coil boot for signs of arcing. This is more common in older vehicles with plug extenders (like 308) but have seen it happen on 550/575.
     
  3. plip

    plip Formula Junior

    Aug 25, 2003
    285
    Switzerland
    Full Name:
    Gianni Olivieri
    HI Zstyle tks for yr kind reply. I recall correctly, but don't quote me on that, the failed gasket was between the head and the runners. Was also thinking abt the fuel pumps and/or fuel filter, also giving that car has been sitting for almost 10 months...are the filters located by the pumps ?
     
  4. PAUL500

    PAUL500 F1 Rookie

    Jun 23, 2013
    3,136
    I am still learning the set up of the 575, but that is showing a misfire in both banks of cylinders, so doubtful its an ecu issue as each bank has its own independent ecu and sensors.

    Its a fault that is being caused by something that supplies the complete engine, so as mentioned more than likely fuel related, the injectors on those cylinders may be slightly more out of tolerance than the rest, so they are the first to be affected, or similarly the plugs in those cylinders may not be the best of all 12 so the first to have problems igniting the mixture.

    Each bank is supplied by a separate pump I believe?, so again the only common thing would be the fuel going through them. The 575 uses a non return supply set up to the fuel rails and so the fuel pump/s has an internal filter.
     
  5. mello

    mello F1 Veteran
    Silver Subscribed

    Jul 12, 2013
    5,035
    CA Bay Area
    Full Name:
    Steve
    I had an intermittent multiple cylinder misfires on my 360 Spider and it turns out to be a bad crankshaft position sensor. It was cheap enough, about $100.00 DIY and took about 15 minutes to R/R.
     
  6. PAUL500

    PAUL500 F1 Rookie

    Jun 23, 2013
    3,136
    Good call as I believe the pair of 575 ecu take signals from only one of these as well. Its located on the bellhousing at the rear of the engine on the 575 and takes the signal from the flywheel
     
  7. zstyle

    zstyle Formula Junior

    Jun 28, 2007
    531
    Fountain Hills
    Full Name:
    Jon
    The fuel filters should be located underneath the vehicle underneath the side undertrays. A pretty simple DIY job. The fuel pumps are more extensive to replace and I have seen fuel eat the rubber isolators clogging the pumps.

    As others have mentioned, the crank position sensors can cause misfires. I believe there should be two crank position sensors on the bell housing underneath a heat shield. One for each bank. You could swap these sensors to see if the issue changes sides.
     
  8. tazandjan

    tazandjan Three Time F1 World Champ
    Lifetime Rossa Owner

    Jul 19, 2008
    37,984
    Clarksville, Tennessee
    Full Name:
    Terry H Phillips
    The fuel filters on a 575M are part of the fuel pump assemblies. No separate fuel filters like the 550.
     
  9. mello

    mello F1 Veteran
    Silver Subscribed

    Jul 12, 2013
    5,035
    CA Bay Area
    Full Name:
    Steve
    If it is the CKS, replace both of them since the engine will not start if either one of them is bad. Mine was working intermittently, so it was hard to diagnose. As a preventive maintenance measure, I would replace both of them even if your engine runs fine due to age.
     
  10. plip

    plip Formula Junior

    Aug 25, 2003
    285
    Switzerland
    Full Name:
    Gianni Olivieri
    tks Guys...will dive into next week it and report back.
     

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