2nd Gen R56 Cooper S Most liked posts in thread: Loud Multiple High Intensity Pre-Ignition knocks?!

  1. Crashton

    Crashton Club Coordinator

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    #2 Crashton, Aug 8, 2013
    If you have enough carbon, your valves could possibly not be closing all the way. You may be hearing a backfire. If that is what it is you are going to burn a valve or possibly drop one into a piston. I recommend you get to the dealer & have this checked out. If you think $1627 was bad wait for the new engine bill. :eek6:

    Good luck & let us know what the cause is. :fingerscrossed:
     
  2. Dave.0

    Dave.0 Helix & RMW Powered
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    #8 Dave.0, Aug 9, 2013
    1. Stop driving
    2. Get your car looked at by the dealer.
    3. Get the carbon job done and hope you did not burn a valve or crack a piston.
     
  3. Systemlord

    Systemlord New Member

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    #16 Systemlord, Feb 18, 2014
    It's been awhile since I updated this thread, I found out why I'm getting pre-ignition. I ran a couple of bottles of BG 44K Fuel System Cleaner, the area in the center of the pistons directly under the spark plugs is spotless! When I ran one of those 5mm diameter cameras down into the cylinders I can see carbon around the outer edge of the piston, I'm going to have a BG service center perform a 3 stage cleaning method similar to a meth injection system on my MCS. I'm looking at getting a meth injection system probably this Summer.

    Systemlord
     
  4. Metalman

    Metalman Well-Known Member
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    #20 Metalman, Feb 18, 2014
    I don't like to think California.... Makes my head hurt on some of the things that goes on in that state...
     
  5. Austinsynthetics

    Austinsynthetics Active Member
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    #3 Austinsynthetics, Aug 8, 2013
    I need to agree with Crashton! I was having similar symptoms, and DID burn a valve in # 3 cylinder. Don't wait and I wouldn't drive it. I had a lot of carbon build up!!! Good luck
     
  6. Crashton

    Crashton Club Coordinator

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    #5 Crashton, Aug 9, 2013
    I don't know for sure if it is carbon, but it sounds like it to me. It could be something else, you need to rule out carbon as a cause. I do know if it is carbon you can have very expensive damage to your engine. If you post where you live someone may be able to help you find a good mechanic who can help in your area.
     
  7. Metalman

    Metalman Well-Known Member
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    #6 Metalman, Aug 9, 2013
    You do use high octane gasoline.... Don't use anything else or you could have detonation as a result with the turbo engine...
     
  8. Dave.0

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    #17 Dave.0, Feb 18, 2014
    Good idea going with Meth on an R56 it cost more than an Oil Catch cans but will keep your motor very CLEAN. You also will not need all the other cleaning products.
     
  9. Jason Montague

    Jason Montague New Member
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    #18 Jason Montague, Feb 18, 2014
    :cornut: My son told me that y'all don't have 93 octane in CA. I'm sorry for that.:nonod:

    Jason
     
  10. Systemlord

    Systemlord New Member

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    #4 Systemlord, Aug 8, 2013
    Last edited: Aug 9, 2013

    I knew I would have needed a carbon cleaning eventually, just didn't think it would be at 49,000 miles. What happens if the dealer walnut blasts when there is carbon on the valve seal or does this kind of thing happen a lot? I could see excess carbon on the back side causing issues with the valve closing fully. Is this what that is, the carbon on the back side of the valve?

    Thanks,
    Systemlord.
     
  11. DneprDave

    DneprDave Well-Known Member
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    #7 DneprDave, Aug 9, 2013
    I wonder if it could be a bad knock sensor. The Engine Control Unit wouldn't get the information it needs to retard the ignition in a pre-ignition situation.

    Dave
     
  12. Crashton

    Crashton Club Coordinator

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    #9 Crashton, Aug 9, 2013
    Could be spark knock, but from the OP's description it sounds like much more. Either way it ain't good.
     
  13. Systemlord

    Systemlord New Member

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    #10 Systemlord, Aug 9, 2013
    I have found out that the pre-ingition only happens when engine is only warm in "Sport Mode", optimal engine temperature is not yet reached. I think it's definitely carbon causing the problem, is there any way I can get this covered under my 6-year warranty?

    I Live in Mission Viejo Southern California.

    I have always used Shell V-Power 91 octane
     
  14. Systemlord

    Systemlord New Member

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    #11 Systemlord, Aug 9, 2013
    Does the 2007 MCS even have a knock sensor?
     
  15. DneprDave

    DneprDave Well-Known Member
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    #12 DneprDave, Aug 9, 2013
    All cars with an ECU have a knock sensor.

    Dave
     
  16. Systemlord

    Systemlord New Member

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    #13 Systemlord, Aug 10, 2013
    Can this explain the sound I'm hearing? One way or the other it's time to get the walnut blasting done now!
     
  17. Systemlord

    Systemlord New Member

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    #14 Systemlord, Aug 25, 2013
    I'm having the walnut blasting done on Monday morning by Irvine Mini in SoCal, don't know what performance improvement to expect...? I have 49,664 on the odometer and she drinks about a half of a quart of oil every 1500 miles since I bought her in March. Runs like a champ which is why I bought it!
     
  18. Systemlord

    Systemlord New Member

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    #15 Systemlord, Aug 29, 2013
    Last edited: Aug 31, 2013
    Periodic backfire inside intake manifold!

    Here's an update, I had the intake valves walnut blasted on Monday at the Irvine Mini dealer and boy was it bad! Even after replacing all of the timing chain components, new valve cover and a carbon cleaning of the intake valves I still have periodic pre-ignition. It doesn't happen very often only on occasion, in hot or cold weather. The only time I don't hear them is WOT when driving my Mini hard.

    Yes I'm using 91 octane gas from Shell, Shell V-Power .

    Thanks for all your help!

    Thank you, Systemlord.
     
  19. Systemlord

    Systemlord New Member

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    #19 Systemlord, Feb 18, 2014
    You ever wonder why CA does have or allow 93 octane?