BMC filters causing problems for airflow sensors? | FerrariChat

BMC filters causing problems for airflow sensors?

Discussion in 'Technical Q&A' started by Geoff, Nov 13, 2004.

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  1. Geoff

    Geoff Rookie

    May 24, 2004
    13
    Japan
    Full Name:
    Garang Geoff
    I have been using a BMC air filter on my 550 for about half a year now. Not only does the car sound better, there was definitely some bhp increase so it was definitely a "happy" mod for me. However, I have now heard of two 911s (a 993 and a 996 Turbo) running on BMC filters which have had damaged airflow sensors. Both owners have been told that the damage was probably (not conclusive) due to the use of oil-based filters which resulted in more oil + dirt getting stuck on the airflow sensors. Has anyone faced such problems on their Ferraris, and in particular on a 550 ? Is there a solution to this "problem" ?
     
  2. ferrarifixer

    ferrarifixer F1 Veteran
    BANNED

    Jul 22, 2003
    8,520
    Melbourne
    Full Name:
    Phil Hughes
    There are many types of air flow meters used. Some are more susceptible than others. The 360 and 550 use different types, and I've put BMC/type filters in both. I have seen some failures of the meter in 360, but it can't be linked directly to the use of oiled filters, as paper filtered air flow meters have caused trouble too.

    In any case, any deposit of oil can be cleaned very carefully.

    When fitting or servicing the filters, be careful to oil them from the "up stream side" , so any oil is drawn into the filter and not lifted off it. And do not over oil them.
     
  3. don_xvi

    don_xvi F1 Rookie

    Nov 1, 2003
    2,934
    Outside Detroit
    Full Name:
    Don the 16th
    It's a common occurrance for K&N filters to foul MAFS. No reason to believe that another brand of oiled filter wouldn't.
    If you have a problem, spray the element with degreaser. This assumes you have a hot-wire type sensor. Do so while it's off and cold. I don't know exactly what type is recommended, perhaps call your local Ford dealership, they've probably seen it and there's either a recommendation out there for what to use or they've figured something out. I'd say go for brake cleaner, but it might be too harsh on a plastic MAFS housing.
     
  4. FTD

    FTD Rookie

    Nov 19, 2003
    36
    New England, USA
    from Radio Shack or Contact East. It's designed to clean grime of switch contacts and printed circuit boards without damaging plastic components.
     
  5. maserati424

    maserati424 Rookie

    Apr 11, 2004
    29
    Berlin, Germany
    Full Name:
    frank gablenz
    I only know that Volkswagen and Bosch have problems with MAFS when siliconspray or oils will beused near the MAFS.
    Bosch make a advice in 2001 for garages here in germany ,for not using silicon spray near the MAFS.
    The same is in my opinion for using filteroil with silicone.
     
  6. 4i2fly

    4i2fly Formula 3

    Apr 16, 2004
    1,333
    SF, Bay Area
    Does anyone know if BMC filter have silicon oil in them, I heard the same thing about silicon oil congesting the injectors...
     
  7. 4i2fly

    4i2fly Formula 3

    Apr 16, 2004
    1,333
    SF, Bay Area
    I just spoke to a BMC dealer in the states and said Ferrari Challenge cars are equipped with BMC air filter from factory. Does anyone know about this and can confirm? Thanks!
     
  8. ferrarifixer

    ferrarifixer F1 Veteran
    BANNED

    Jul 22, 2003
    8,520
    Melbourne
    Full Name:
    Phil Hughes
    saw your pm before this post...

    But no 360C have paper, N-GT have BMC. You can just paste my reply......
     
  9. 4i2fly

    4i2fly Formula 3

    Apr 16, 2004
    1,333
    SF, Bay Area
    I just got an e-mail from BMC Italy and they confirmed the oil used in their filter is not silicon based. Here's the message with contact information:

    "Dear Matt,

    Thank you for your e-mail and for your interest in BMC products.

    The oil that we use is not silicone based.

    Kind regards,

    BMC srl
    Caroline Dunphy Export-dept"
     
  10. TCM

    TCM Formula Junior

    Nov 10, 2003
    552
    Tyngsborough, MA
    As stated above, this is a very common problem among many makes MAFS. The sensor wires can be clenaed though with contact solution and or Simple Green belive it or not! That being said, most people have now just gone back to paper filters as the performance advantage gained is not worth the hassle in fixing or replacing the MAFS.
     
  11. ferrarifixer

    ferrarifixer F1 Veteran
    BANNED

    Jul 22, 2003
    8,520
    Melbourne
    Full Name:
    Phil Hughes
    Wrong TCM. People spend 10's of thousands of dollars to gain what a $100 filter can give.

    The stopwatch shows the proof, forget dyno's, it's response time and acceleration that improves....here we go again.....

    A free flowing filter gives similar gains to a lighter flywheel. Minimal measurable power and torque gains....but the stopwatch DOES NOT lie.
     

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